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any accept). That is, while a DTM must follow only one branch of computation, an NTM can be imagined as a computation tree, branching into many possible computational pathways at each step (see image). If at least one branch of the tree halts with an "accept" condition, then the NTM accepts the input. In this way, an NTM can be thought of as simultaneously exploring all computational possibilities in parallel and selecting an accepting branch. NTMs are not meant to be physically realizable models, they are simply theoretically interesting abstract machines that give rise to a number of interesting complexity classes (which often do have physically realizable equivalent definitions).
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definition of a probabilistic Turing machine specifies two transition functions, so that the selection of transition function at each step resembles a coin flip. The randomness introduced at each step of the computation introduces the potential for error; that is, strings that the Turing machine is meant to accept may on some occasions be rejected and strings that the Turing machine is meant to reject may on some occasions be accepted. As a result, the complexity classes based on the probabilistic Turing machine are defined in large part around the amount of error that is allowed. Formally, they are defined using an error probability
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finite set of elementary instructions such as "in state 42, if the symbol seen is 0, write a 1; if the symbol seen is 1, change into state 17; in state 17, if the symbol seen is 0, write a 1 and change to state 6". The Turing machine starts with only the input string on its tape and blanks everywhere else. The TM accepts the input if it enters a designated accept state and rejects the input if it enters a reject state. The deterministic Turing machine (DTM) is the most basic type of Turing machine. It uses a fixed set of rules to determine its future actions (which is why it is called "
5454:. However, this definition gives no indication of whether this inclusion is strict. For time and space requirements, the conditions under which the inclusion is strict are given by the time and space hierarchy theorems, respectively. They are called hierarchy theorems because they induce a proper hierarchy on the classes defined by constraining the respective resources. The hierarchy theorems enable one to make quantitative statements about how much more additional time or space is needed in order to increase the number of problems that can be solved. 6586: 6204: 31: 7220: 9075: 661: 469: 221:. They are defined in terms of the computational difficulty of solving the problems contained within them with respect to particular computational resources like time or memory. More formally, the definition of a complexity class consists of three things: a type of computational problem, a model of computation, and a bounded computational resource. In particular, most complexity classes consist of 6658:
proof system by having the computationally unbounded prover solve for whether a string is in a language and then sending a trustworthy "YES" or "NO" to the verifier), so the verifier must conduct an "interrogation" of the prover by "asking it" successive rounds of questions, accepting only if it develops a high degree of confidence that the string is in the language.
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computational branch one-by-one). Hence, the two are equivalent in terms of computability. However, simulating an NTM with a DTM often requires greater time and/or memory resources; as will be seen, how significant this slowdown is for certain classes of computational problems is an important question in computational complexity theory.
6684:(the set of decision problems for which the problem instances, when the answer is "YES", have proofs verifiable in polynomial time by a deterministic Turing machine) is a proof system in which the proof is constructed by an unmentioned prover and the deterministic Turing machine is the verifier. For this reason, 3754:, for instance, is closed under all Boolean operations, and under quantification over polynomially sized domains. Closure properties can be helpful in separating classes—one possible route to separating two complexity classes is to find some closure property possessed by one class but not by the other. 615:
resource requirements of problems and not the resource requirements that depend upon how a physical computer is constructed. For example, in the real world different computers may require different amounts of time and memory to solve the same problem because of the way that they have been engineered.
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the two-tape Turing machine is equivalent to the single-tape Turing machine). In the two-tape Turing machine model, one tape is the input tape, which is read-only. The other is the work tape, which allows both reading and writing and is the tape on which the Turing machine performs computations. The
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has unlimited computational power while the verifier has bounded computational power (the standard definition of interactive proof systems defines the verifier to be polynomially-time bounded). The prover, however, is untrustworthy (this prevents all languages from being trivially recognized by the
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These relationships answer fundamental questions about the power of nondeterminism compared to determinism. Specifically, Savitch's theorem shows that any problem that a nondeterministic Turing machine can solve in polynomial space, a deterministic Turing machine can also solve in polynomial space.
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The deterministic Turing machine (DTM) is a variant of the nondeterministic Turing machine (NTM). Intuitively, an NTM is just a regular Turing machine that has the added capability of being able to explore multiple possible future actions from a given state, and "choosing" a branch that accepts (if
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Mechanically, a Turing machine (TM) manipulates symbols (generally restricted to the bits 0 and 1 to provide an intuitive connection to real-life computers) contained on an infinitely long strip of tape. The TM can read and write, one at a time, using a tape head. Operation is fully determined by a
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DTMs can be viewed as a special case of NTMs that do not make use of the power of nondeterminism. Hence, every computation that can be carried out by a DTM can also be carried out by an equivalent NTM. It is also possible to simulate any NTM using a DTM (the DTM will simply compute every possible
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is a mathematical model of a general computing machine. It is the most commonly used model in complexity theory, owing in large part to the fact that it is believed to be as powerful as any other model of computation and is easy to analyze mathematically. Importantly, it is believed that if there
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captures the full power of interactive proof systems with deterministic (polynomial-time) verifiers because it can be shown that for any proof system with a deterministic verifier it is never necessary to need more than a single round of messaging between the prover and the verifier. Interactive
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A probabilistic Turing machine is similar to a deterministic Turing machine, except rather than following a single transition function (a set of rules for how to proceed at each step of the computation) it probabilistically selects between multiple transition functions at each step. The standard
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is the set of languages that are decidable by polynomial-size circuit families. It turns out that there is a natural connection between circuit complexity and time complexity. Intuitively, a language with small time complexity (that is, requires relatively few sequential operations on a Turing
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The study of the relationships between complexity classes is a major area of research in theoretical computer science. There are often general hierarchies of complexity classes; for example, it is known that a number of fundamental time and space complexity classes relate to each other in the
7972:), however, contain strings of differing lengths, so languages cannot be fully captured by a single circuit (this contrasts with the Turing machine model, in which a language is fully described by a single Turing machine that can act on any input size). A language is thus represented by a 7077:
is defined as the class of languages with an interactive proof in which the verifier sends a random string to the prover, the prover responds with a message, and the verifier either accepts or rejects by applying a deterministic polynomial-time function to the message from the prover.
3952:, rather than all polynomials, which allows for such large discrepancies. It turns out, however, that the set of all polynomials is the smallest class of functions containing the linear functions that is also closed under addition, multiplication, and composition (for instance, 631:), the Turing machine is used to define most basic complexity classes. With the Turing machine, instead of using standard units of time like the second (which make it impossible to disentangle running time from the speed of physical hardware) and standard units of memory like 11945:
as promise problems provides little additional insight into their nature. However, there are some complexity classes for which formulating them as promise problems have been useful to computer scientists. Promise problems have, for instance, played a key role in the study of
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algorithm. There may be an algorithm, for instance, that solves a particular problem in exponential time, but if the most efficient algorithm for solving this problem runs in polynomial time then the inherent time complexity of that problem is better described as polynomial.
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complexity required to solve computational problems. Complexity theorists are thus generally concerned with finding the smallest complexity class that a problem falls into and are therefore concerned with identifying which class a computational problem falls into using the
5137: 5606: 5760: 635:, the notion of time is abstracted as the number of elementary steps that a Turing machine takes to solve a problem and the notion of memory is abstracted as the number of cells that are used on the machine's tape. These are explained in greater detail below. 1055:
In computational complexity theory, theoretical computer scientists are concerned less with particular runtime values and more with the general class of functions that the time complexity function falls into. For instance, is the time complexity function a
3916:, yet the runtime of the second grows considerably faster than the runtime of the first as the input size increases. One might ask whether it would be better to define the class of "efficiently solvable" problems using some smaller polynomial bound, like 554:, the algorithm answers "yes, this number is prime". This "yes-no" format is often equivalently stated as "accept-reject"; that is, an algorithm "accepts" an input string if the answer to the decision problem is "yes" and "rejects" if the answer is "no". 7379: 1086:
of an algorithm with respect to the Turing machine model is the number of cells on the Turing machine's tape that are required to run an algorithm on a given input size. Formally, the space complexity of an algorithm implemented with a Turing machine
3408:, which follows intuitively from the fact that, since writing to a cell on a Turing machine's tape is defined as taking one unit of time, a Turing machine operating in polynomial time can only write to polynomially many cells. It is suspected that 4090:). Since we would like composing one efficient algorithm with another efficient algorithm to still be considered efficient, the polynomials are the smallest class that ensures composition of "efficient algorithms". (Note that the definition of 6254:(zero-error probabilistic polynomial time), the class of problems solvable in polynomial time by a probabilistic Turing machine with error probability 0. Intuitively, this is the strictest class of probabilistic problems because it demands 2413:
a polynomial speedup over being able to explore only a single branch. Furthermore, it would follow that if there exists a proof for a problem instance and that proof can be quickly be checked for correctness (that is, if the problem is in
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of an algorithm with respect to the Turing machine model is the number of steps it takes for a Turing machine to run an algorithm on a given input size. Formally, the time complexity for an algorithm implemented with a Turing machine
3334: 3232: 10126: 6362:(bounded-error probabilistic polynomial time), the class of problems solvable in polynomial time by a probabilistic Turing machine with error probability less than 1/3 (for both strings in the language and not in the language). 1866: 557:
While some problems cannot easily be expressed as decision problems, they nonetheless encompass a broad range of computational problems. Other types of problems that certain complexity classes are defined in terms of include:
6384:, which if true would mean that randomness does not increase the computational power of computers, i.e. any probabilistic Turing machine could be simulated by a deterministic Turing machine with at most polynomial slowdown. 4160:. A reduction is a transformation of one problem into another problem, i.e. a reduction takes inputs from one problem and transforms them into inputs of another problem. For instance, you can reduce ordinary base-10 addition 1782: 7065:, the prover was not able to see the coins utilized by the verifier in its probabilistic computation—it was only able to see the messages that the verifier produced with these coins. For this reason, the coins are called 3089: 380: 11374: 8836:. In other words, any problem that can be solved in polynomial time by a deterministic Turing machine can also be solved by a polynomial-size circuit family. It is further the case that the inclusion is proper, i.e. 11306: 3828: 8833: 6477: 6637:. The parties interact by exchanging messages, and an input string is accepted by the system if the verifier decides to accept the input on the basis of the messages it has received from the prover. The prover 11202: 11158: 4385:
Generally, reductions are used to capture the notion of a problem being at least as difficult as another problem. Thus we are generally interested in using a polynomial-time reduction, since any problem
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New York: W. H. Freeman & Co., 1979. The standard reference on NP-Complete problems - an important category of problems whose solutions appear to require an impractically long time to compute.
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are a generalization of decision problems in which the input to a problem is guaranteed ("promised") to be from a particular subset of all possible inputs. Recall that with a decision problem
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While there might seem to be an obvious difference between the class of problems that are efficiently solvable and the class of problems whose solutions are merely efficiently checkable,
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has. The output to a counting problem is thus a number, in contrast to the output for a decision problem, which is a simple yes/no (or accept/reject, 0/1, or other equivalent scheme).
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is a subset, but it is unknown whether they are equal sets, then the line is lighter and dotted. Technically, the breakdown into decidable and undecidable pertains more to the study of
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has a number of properties that make it highly useful in the study of the relationships between complexity classes. In particular, it is helpful in investigating problems related to
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Savitch's theorem establishes the relationship between deterministic and nondetermistic space resources. It shows that if a nondeterministic Turing machine can solve a problem using
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in the resources required to solve particular computational problems as the input size increases. For example, the amount of time it takes to solve problems in the complexity class
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A computational problem can then be defined in terms of a Turing machine as the set of input strings that a particular Turing machine accepts. For example, the primality problem
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a language (recall that "problem" and "language" are largely synonymous in computability and complexity theory) if it accepts all inputs that are in the language and is said to
9203: 6393:(probabilistic polynomial time), the set of languages solvable by a probabilistic Turing machine in polynomial time with an error probability of less than 1/2 for all strings. 6337:
is similarly defined except the roles are flipped: error is not allowed for strings in the language but is allowed for strings not in the language. Taken together, the classes
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is the set of languages that can be solved by circuit families that are restricted not only to having polynomial-size but also to having polylogarithmic depth. The class
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By providing an abstract mathematical representations of computers, computational models abstract away superfluous complexities of the real world (like differences in
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The time and space hierarchy theorems form the basis for most separation results of complexity classes. For instance, the time hierarchy theorem establishes that
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Similarly, any problem that a nondeterministic Turing machine can solve in exponential space, a deterministic Turing machine can also solve in exponential space.
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are efficiently solvable. And since computing the number of certificates is at least as hard as determining whether a certificate exists, it must follow that if
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Closure properties are one of the key reasons many complexity classes are defined in the way that they are. Take, for example, a problem that can be solved in
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Promise problems make for a more natural formulation of many computational problems. For instance, a computational problem could be something like "given a
9997: 7574:. Not only does this model provide an intuitive connection between computation in theory and computation in practice, but it is also a natural model for 1788: 8643:
machine), also has a small circuit complexity (that is, requires relatively few Boolean operations). Formally, it can be shown that if a language is in
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adds any computational power to computers and whether problems having solutions that can be quickly checked for correctness can also be quickly solved.
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on the maximum amount of resources that the most efficient algorithm takes to solve them. More specifically, complexity classes are concerned with the
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Classes of decision problems—that is, classes of problems defined as formal languages—thus translate naturally to promise problems, where a language
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time complexity classes, these are extremely narrow classes as sublinear times do not even enable a Turing machine to read the entire input (because
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that the Turing machine must halt on all inputs). A Turing machine that "solves" a problem is generally meant to mean one that decides the language.
13258: 8441:, circuit complexity classes are defined in terms of circuit size — the number of vertices in the circuit. The size complexity of a circuit family 13231: 3047: 673:
exists an algorithm that solves a particular problem then there also exists a Turing machine that solves that same problem (this is known as the
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to a planar graph. However, it is more straightforward to define this as a promise problem in which the input is promised to be a planar graph.
11548:, determine whether or not..." This is often stated as a decision problem, where it is assumed that there is some translation schema that takes 9821:
asks whether there exists a proof of membership (a certificate) for the input that can be checked for correctness in polynomial time. The class
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A comparison of deterministic and nondeterministic computation. If any branch on the nondeterministic computation accepts then the NTM accepts.
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are the most commonly used models of computation, many complexity classes are defined in terms of other computational models. In particular,
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of a TM on a particular input is the number of elementary steps that the Turing machine takes to reach either an accept or reject state. The
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values 0 and 1), the input bits are represented by source vertices (vertices with no incoming edges), and all non-source vertices represent
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a language if it additionally rejects all inputs that are not in the language (certain inputs may cause a Turing machine to run forever, so
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is the class of problems whose polynomial time verifiers need only receive the empty string as their certificate), it is not known whether
13549: 8802: 6438: 2879:). However, there are a meaningful number of problems that can be solved in logarithmic space. The definitions of these classes require a 522:". In terms of the theory of computation, a decision problem is represented as the set of input strings that a computer running a correct 797:
Complexity classes group computational problems by their resource requirements. To do this, computational problems are differentiated by
496:. The primality example above, for instance, is an example of a decision problem as it can be represented by the yes–no question "is the 8604:. The familiar function classes follow naturally from this; for example, a polynomial-size circuit family is one such that the function 13514: 17: 13362: 13999: 13176: 11167: 11123: 7625:). One logic gate is designated the output gate, and represents the end of the computation. The input/output behavior of a circuit 13267: 13204: 11619: 11077: 10898: 2310:
This equivalence between the nondeterministic definition and the verifier definition highlights a fundamental connection between
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Within this formulation, it can be seen that decision problems are just the subset of promise problems with the trivial promise
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and the procedure is restricted to one round (that is, the prover sends only a single, full proof—typically referred to as the
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is often said to be the class of problems that can be solved "quickly" or "efficiently" by a deterministic computer, since the
10300: 2912: 14009: 13356: 13212: 7135: 9054:, however gates are allowed to have unbounded fan-in (that is, the AND and OR gates can be applied to more than two bits). 5132:{\displaystyle {\mathsf {NSPACE}}\left(f\left(n\right)\right)\subseteq {\mathsf {DSPACE}}\left(f\left(n\right)^{2}\right).} 2347: 394:. For this reason, computational problems are often synonymously referred to as languages, since strings of bits represent 5601:{\displaystyle {\mathsf {DTIME}}{\big (}f(n){\big )}\subsetneq {\mathsf {DTIME}}{\big (}f(n)\cdot \log ^{2}(f(n)){\big )}} 3836:, for instance, is one important complement complexity class, and sits at the center of the unsolved problem over whether 716:
from above is the set of strings (representing natural numbers) that a Turing machine running an algorithm that correctly
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is the set of strings representing natural numbers that, when input into a computer running an algorithm that correctly
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rate as the input size increases, which is comparatively slow compared to problems in the exponential complexity class
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To make concrete the notion of a "computer", in theoretical computer science problems are analyzed in the context of a
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over determinism with regards to the ability to quickly find a solution to a problem; that is, being able to explore
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is the class of promise problems that are solvable in deterministic polynomial time. That is, the promise problem
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is the class of problems solvable in exponential space by a nondeterministic Turing machine. Or more formally,
2898:) is then defined as the class of problems solvable in logarithmic space on a deterministic Turing machine and 11958:
The following table shows some of the classes of problems that are considered in complexity theory. If class
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that are practically useful do in fact have low order polynomial runtimes, and almost all problems outside of
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arises from the fact that the number of solutions to a problem equals the number of accepting branches in a
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and solution verifiability. Furthermore, it also provides a useful method for proving that a language is in
193:. The relationships between classes often answer questions about the fundamental nature of computation. The 13429: 12048: 10569: 7741: 7045: 5911: 5799: 3133:
is the class of problems solvable in polynomial space by a nondeterministic Turing machine. More formally,
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space complexity of the Turing machine is measured as the number of cells that are used on the work tape.
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is a notable class because it can be equivalently defined as the class of languages that have efficient
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Any particular circuit has a fixed number of input vertices, so it can only act on inputs of that size.
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that are practically useful do not have any known algorithms with small exponential runtimes, i.e. with
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Promise problems provide an alternate definition for standard complexity classes of decision problems.
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is a simple proof system in which the verifier is restricted to being a deterministic polynomial-time
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proof systems that provide greater computational power over standard complexity classes thus require
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The relationships between the fundamental probabilistic complexity classes. BQP is a probabilistic
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so that it is possible for the machine to store the entire input (it can be shown that in terms of
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with at most polynomial slowdown. Of particular importance, the set of problems that are hard for
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are actually at the center of one of the most famous unsolved problems in computer science: the
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is probabilistic polynomial-time and the proof system satisfies two properties: for a language
6715: 6709: 5990: 5930: 5904: 5877: 5458: 5171: 4982: 4574: 4350: 4151: 3680:{\displaystyle {\mathsf {NEXPSPACE}}=\bigcup _{k\in \mathbb {N} }{\mathsf {NSPACE}}(2^{n^{k}})} 2464: 386:; for example, in the primality example the natural numbers could be represented as strings of 89:, and are differentiated by their time or space (memory) requirements. For instance, the class 10202: 4946: 4105: 3919: 3565:{\displaystyle {\mathsf {EXPSPACE}}=\bigcup _{k\in \mathbb {N} }{\mathsf {DSPACE}}(2^{n^{k}})} 1153: 979: 179:
relation). However, many relationships are not yet known; for example, one of the most famous
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is the class of problems solvable in exponential space by a deterministic Turing machine and
2747:{\displaystyle {\mathsf {NEXPTIME}}=\bigcup _{k\in \mathbb {N} }{\mathsf {NTIME}}(2^{n^{k}})} 2318:—simply identify a suitable certificate and show that it can be verified in polynomial time. 1617: 1519: 1421: 1326: 785:
of an NTM is the maximum number of cells that the NTM uses on any branch of its computation.
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is the class of problems solvable in polynomial space by a deterministic Turing machine and
2638:{\displaystyle {\mathsf {EXPTIME}}=\bigcup _{k\in \mathbb {N} }{\mathsf {DTIME}}(2^{n^{k}})} 2274: 297:?" is a computational problem. A computational problem is mathematically represented as the 13903: 13553: 13254: 12576: 11983: 8944: 8580: 8370: 8050: 7937: 7531: 7507: 6744: 6371: 5920: 4909: 3690: 3348: 1065: 1061: 747:
is the number of cells on its tape that it uses to reach either an accept or reject state.
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polynomial time Turing machine, referred to as the verifier, that takes as input a string
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Includes a diagram showing the hierarchy of complexity classes and how they fit together.
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is also at the center of the important unsolved problem in computer science over whether
4626: 4163: 3743: 3329:{\displaystyle {\mathsf {NPSPACE}}=\bigcup _{k\in \mathbb {N} }{\mathsf {NSPACE}}(n^{k})} 3100: 643: 604: 493: 69:
In general, a complexity class is defined in terms of a type of computational problem, a
4979:
space, i.e. in the square of the space. Formally, Savitch's theorem states that for any
3227:{\displaystyle {\mathsf {PSPACE}}=\bigcup _{k\in \mathbb {N} }{\mathsf {DSPACE}}(n^{k})} 13382: 12695: 12072: 11807: 11669: 11487: 11057: 10836: 10768: 10748: 10467: 10447: 10389: 10369: 10349: 10254: 10234: 10160: 9932: 9776: 9756: 9662: 9530: 9267: 9212: 9059: 8700: 8607: 8417: 8397: 8279: 8259: 8239: 8219: 8157: 8137: 8117: 8097: 8077: 7913: 7806: 7648: 7628: 7584: 7214: 6954: 6934: 6852: 6832: 6776: 6640: 6620: 6600: 6345:
encompass all of the problems that can be solved by probabilistic Turing machines with
6314: 6294: 6274: 6127: 6107: 6034: 6014: 5970: 5950: 4840: 4816: 4786: 4758: 4716: 4696: 4672: 4644: 4493: 4469: 4449: 4429: 4409: 4389: 4269: 4249: 4229: 4209: 4189: 3747: 2844: 2187: 2167: 2102: 2082: 2062: 2035: 2029: 2011: 1991: 1971: 1951: 1931: 1904: 1209: 1189: 1090: 1035: 1015: 916: 502: 277: 13288: 9801:
can be defined both in terms of nondeterminism and in terms of a verifier (i.e. as an
6704:
verifiers, which means that the verifier's questions to the prover are computed using
1245:
Complexity classes are often defined using granular sets of complexity classes called
13923: 13476: 13442: 13352: 13278: 13208: 13200: 13193: 10121:{\displaystyle f(w)={\Big |}{\big \{}c\in \{0,1\}^{p(|w|)}:V(w,c)=1{\big \}}{\Big |}} 9809:
be equivalently defined in terms of a verifier. Recall that a decision problem is in
6507:
does not allow error for strings not in the language. Hence, if a problem is in both
6366:
is the most practically relevant of the probabilistic complexity classes—problems in
551: 298: 214: 47: 13531: 9000: 6735:
The most general complexity class arising out of this characterization is the class
5919:
that can toss random coins. These classes help to better describe the complexity of
1889:
is that it can be equivalently defined as the class of problems whose solutions are
13887: 13777: 13709: 13699: 13565: 13378: 13344: 11998: 10657: 10187: 9174: 9144: 9136: 7969: 7666: 7201: 6594: 6528: 6519:
not in the language (i.e. no error whatsoever), which is exactly the definition of
6358: 6250: 6235: 6217: 5822: 2823: 1861:{\displaystyle {\mathsf {NP}}=\bigcup _{k\in \mathbb {N} }{\mathsf {NTIME}}(n^{k})} 1083: 1077: 782: 744: 562: 489: 473: 244: 234: 222: 120: 104: 82: 78: 63: 10157:
equals the size of the set containing all of the polynomial-size certificates for
4609:
Note that reductions can be defined in many different ways. Common reductions are
1777:{\displaystyle {\mathsf {P}}=\bigcup _{k\in \mathbb {N} }{\mathsf {DTIME}}(n^{k})} 884:
Note that the study of complexity classes is intended primarily to understand the
34:
A representation of the relationships between several important complexity classes
13882: 13872: 13829: 13819: 13812: 13802: 13792: 13750: 13745: 13740: 13724: 13704: 13682: 13677: 13672: 13660: 13655: 13650: 13645: 13538: 13343:. Lecture Notes in Computer Science. Vol. 3895. Springer. pp. 254–290. 12600: 12545: 12348: 11538: 11376:. With decision problems it is thus simpler to simply define the problem as only 10692: 10663: 10573: 10560: 9288: 9148: 9030: 9024: 8949: 8438: 8437:
While complexity classes defined using Turing machines are described in terms of
7965: 7567: 7562: 7061:(Arthur–Merlin protocol). In the definition of interactive proof systems used by 7057: 6737: 6668: 6597:
that model computation as the exchange of messages between two parties: a prover
6585: 6566: 6534: 6389: 6353: 6346: 6263: 6241: 6223: 5870: 5864: 5853: 5846: 5840: 5834: 5816: 5810: 4618: 3750:. Moreover, they might also be closed under a variety of quantification schemes. 3121: 2838: 1875: 1690: 1677: 1662: 909: 903: 774: 740: 591: 567: 428: 395: 252: 230: 147: 135: 116: 96: 74: 59: 13141: 6203: 1893:
by a deterministic Turing machine in polynomial time. That is, a language is in
13877: 13765: 13687: 13640: 13463: 13324: 13168: 13164: 12500: 10608:, then the functions that determine the number of certificates for problems in 10582: 9559: 9008: 8799: 7557: 6673: 5916: 5791: 4614: 4610: 3115: 2834: 1673: 1262: 807: 717: 655: 624: 497: 272: 239: 226: 141: 128: 91: 86: 13117: 10895:
Specifically, a promise problem is defined as a pair of non-intersecting sets
7219: 6564:. Interactive proofs generalize the proofs definition of the complexity class 95:
is the set of decision problems solvable by a deterministic Turing machine in
13988: 13561: 13545: 13438: 13184: 9039: 8394:(the circuit with the same number of input vertices as the number of bits in 7090:
is the number of messages exchanged (so in the generalized form the standard
2884: 729: 686: 391: 13129: 6692:(deterministic interactive proof), though it is rarely referred to as such. 3084:{\displaystyle {\mathsf {L}}\subseteq {\mathsf {NL}}\subseteq {\mathsf {P}}} 30: 11545: 9230: 6571: 519: 375:{\displaystyle {\texttt {PRIME}}=\{n\in \mathbb {N} |n{\text{ is prime}}\}} 294: 180: 4837:(since there could be many problems that are equally hard, more precisely 2426:). However, the overwhelming majority of computer scientists believe that 301:
of answers to the problem. In the primality example, the problem (call it
13755: 13665: 13425: 13337:
Theoretical Computer Science. Lecture Notes in Computer Science, vol 3895
13090: 11369:{\displaystyle \Pi _{\text{ACCEPT}}\cup \Pi _{\text{REJECT}}=\{0,1\}^{*}} 10591: 9135:
While most complexity classes studied by computer scientists are sets of
8885: 7193:
Other complexity classes defined using interactive proof systems include
4943:
space, then a deterministic Turing machine can solve the same problem in
4865: 4226:
to their base-2 notation (e.g. 5+7 becomes 101+111). Formally, a problem
3739: 3091:. However, it is not known whether any of these relationships is proper. 2335: 798: 639: 399: 184: 13348: 11301:{\displaystyle \Pi _{\text{ACCEPT}}\cap \Pi _{\text{REJECT}}=\emptyset } 9074: 4887:-complete problem that can be solved in polynomial time would mean that 3701:. This class is extremely broad: it is known to be a strict superset of 664:
An illustration of a Turing machine. The "B" indicates the blank symbol.
488:
The most commonly analyzed problems in theoretical computer science are
13867: 13692: 13570:
Computers and Intractability: A Guide to the Theory of NP-Completeness.
13377:. Handbook of Theoretical Computer Science. Elsevier. pp. 67–161. 13239: 13188: 8625: 7610: 3876:
time (that is, in linear time) and one that can be solved in, at best,
3823:{\displaystyle {\textsf {co-X}}=\{L|{\overline {L}}\in {\mathsf {X}}\}} 1057: 812: 11953: 2079:
for which there exists a polynomial-time deterministic Turing machine
13862: 13575: 10192:
Counting problems are a subset of a broader class of problems called
9659:
such that there is a polynomial time nondeterministic Turing machine
9563: 6387:
The broadest class of efficiently-solvable probabilistic problems is
523: 268: 13334:. In Goldreich, Oded; Rosenberg, Arnold L.; Selman, Alen L. (eds.). 9233:(the answer is a simple yes/no); the corresponding counting problem 8828:{\displaystyle {\mathsf {\color {Blue}P}}\subset {\textsf {P/poly}}} 6472:{\displaystyle {\textsf {ZPP}}={\textsf {RP}}\cap {\textsf {co-RP}}} 739:
Turing machines enable intuitive notions of "time" and "space". The
660: 13857: 13852: 13797: 13620: 12120: 12096: 11986:, but is useful for putting the complexity classes in perspective. 10196:. A function problem is a type of problem in which the values of a 7622: 7614: 7571: 7549: 7501: 6680:—to the verifier). Put another way, in the definition of the class 3735: 3446: 3425: 2517: 468: 325:) is represented by the set of all natural numbers that are prime: 201:
problem, for instance, is directly related to questions of whether
171: 165: 10564:, the class of efficiently solvable functions. More specifically, 9287:
Thus, whereas decision problems are represented mathematically as
3765:, which consists of the complements of the languages contained in 646:, but this approach is less frequently used in complexity theory. 13847: 12144: 10628:(it is not known whether this holds in the reverse, i.e. whether 7618: 7525: 4743: 3440: 2513: 817: 620:
speed) that obstruct an understanding of fundamental principles.
579: 382:. In the theory of computation, these answers are represented as 159: 13954: 13949: 13824: 13807: 13431:
Automata, Computability and Complexity: Theory and Applications
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input variables. A circuit family is said to decide a language
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A number of important complexity classes are defined using the
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is not in the language. Intuitively, the certificate acts as a
176: 153: 5158:(since the square of an exponential is still an exponential). 3734:
properties. For example, decision classes may be closed under
777:
of an NTM is the maximum number of steps that the NTM uses on
13944: 13939: 13760: 13541:: A huge list of complexity classes, a reference for experts. 13373:
Johnson, David S. (1990). "A Catalog of Complexity Classes".
13042: 12526: 12474: 12465: 12458: 12435: 12413: 12390: 12381: 12374: 12320: 12294: 12285: 12278: 12255: 12246: 12239: 12210: 12201: 12194: 12156: 12132: 12108: 11197:{\displaystyle \Pi _{\text{ACCEPT}}\cup \Pi _{\text{REJECT}}} 11153:{\displaystyle \Pi _{\text{ACCEPT}}\cup \Pi _{\text{REJECT}}} 6333: 6229: 5150:(since the square of a polynomial is still a polynomial) and 3832: 642:
to define complexity classes without referring to a concrete
13080: 13078: 13076: 13074: 12588: 12564: 12557: 12535: 12519: 12512: 12490: 12483: 12451: 12444: 12406: 12399: 12367: 12360: 12310: 12303: 12271: 12264: 12232: 12187: 12180: 12084: 12060: 12021: 12012: 4094:
is also useful because, empirically, almost all problems in
13772: 13630: 12596: 12572: 12541: 12496: 12419: 12344: 12329: 12316: 12218: 12164: 12140: 12116: 12092: 12068: 12044: 12029: 11994: 11988: 11655:{\displaystyle (\Pi _{\text{ACCEPT}},\Pi _{\text{REJECT}})} 11113:{\displaystyle (\Pi _{\text{ACCEPT}},\Pi _{\text{REJECT}})} 10934:{\displaystyle (\Pi _{\text{ACCEPT}},\Pi _{\text{REJECT}})} 6271:
if there is a probabilistic polynomial-time Turing machine
4898: 4156:
Many complexity classes are defined using the concept of a
632: 9007:
is also helpful in the general study of the properties of
8863:{\displaystyle {\textsf {P}}\subsetneq {\textsf {P/poly}}} 7073:; that is, the prover is able to see the coins. Formally, 874:{\displaystyle {\mathsf {P}}\subseteq {\mathsf {EXPTIME}}} 13787: 13719: 13714: 13635: 13625: 13071: 13030: 12994: 12970: 12333: 11043:{\displaystyle \Pi _{\text{REJECT}}\subseteq \{0,1\}^{*}} 10989:{\displaystyle \Pi _{\text{ACCEPT}}\subseteq \{0,1\}^{*}} 9550:
Counting problems arise in a number of fields, including
9495: 9113: 9107: 7606: 5888: 5882: 3761:
that is not closed under negation has a complement class
3401:{\displaystyle {\mathsf {P}}\subseteq {\mathsf {PSPACE}}} 3034:{\displaystyle {\mathsf {NL}}={\mathsf {NSPACE}}(\log n)} 387: 12924: 12922: 12909: 12907: 12820: 10580:
can be thought of as the function problem equivalent of
10568:
is the set of function problems that can be solved by a
10336:{\displaystyle R\subseteq \Sigma ^{*}\times \Sigma ^{*}} 9022:
that have interesting properties in their own right are
6211:
class and is described in the quantum computing section.
2966:{\displaystyle {\mathsf {L}}={\mathsf {DSPACE}}(\log n)} 2418:), then there also exists an algorithm that can quickly 13107: 13105: 12808: 7223:
Example Boolean circuit computing the Boolean function
6589:
General representation of an interactive proof protocol
6311:
always rejects and if a string is in the language then
6215:
The fundamental randomized time complexity classes are
10590:
provides some insight into both counting problems and
9291:, counting problems are represented mathematically as 9038:. The depth of a circuit is the length of the longest 7183:{\displaystyle {\mathsf {AM}}\subseteq {\mathsf {IP}}} 7010: 6908: 6526:
Important randomized space complexity classes include
6352:
Loosening the error requirements further to allow for
13228:
Computer Science 522: Computational Complexity Theory
12982: 12946: 12934: 12919: 12904: 12892: 12844: 12753: 12718: 12698: 12672: 12643: 11890: 11863: 11830: 11810: 11751: 11695: 11672: 11622: 11609:, for instance, can be defined as a promise problem: 11558: 11510: 11490: 11436: 11409: 11382: 11317: 11268: 11241: 11214: 11170: 11126: 11080: 11060: 11004: 10950: 10901: 10859: 10839: 10833:. A promise problem loosens the input requirement on 10794: 10771: 10751: 10706: 10523: 10494: 10470: 10450: 10412: 10392: 10372: 10352: 10303: 10280: 10257: 10237: 10205: 10163: 10134: 10000: 9955: 9935: 9899: 9846: 9779: 9759: 9730: 9685: 9665: 9612: 9533: 9504: 9455: 9428: 9399: 9354: 9301: 9270: 9239: 9215: 9187: 8967: 8908: 8842: 8805: 8759: 8723: 8703: 8649: 8610: 8583: 8554: 8518: 8447: 8420: 8400: 8373: 8302: 8296:
is in the language represented by the circuit family
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does not allow error for strings in the language and
6441: 6317: 6297: 6277: 6150: 6130: 6110: 6057: 6037: 6017: 5993: 5973: 5953: 5933: 5625: 5470: 5420: 5348: 5308: 5249: 5190: 5023: 4985: 4949: 4920: 4843: 4819: 4789: 4761: 4719: 4699: 4675: 4647: 4577: 4549: 4516: 4496: 4472: 4452: 4432: 4412: 4392: 4353: 4325: 4292: 4272: 4252: 4232: 4212: 4192: 4166: 4108: 4038: 3958: 3922: 3882: 3853: 3775: 3579: 3467: 3365: 3241: 3142: 3050: 2980: 2915: 2853: 2781: 2652: 2546: 2473: 2432: 2374:{\displaystyle {\mathsf {P}}\subseteq {\mathsf {NP}}} 2350: 2277: 2213: 2190: 2170: 2125: 2105: 2085: 2065: 2038: 2014: 1994: 1974: 1954: 1934: 1907: 1791: 1710: 1620: 1563: 1522: 1465: 1424: 1370: 1329: 1275: 1212: 1192: 1156: 1113: 1093: 1038: 1018: 982: 939: 919: 835: 698: 532: 505: 438: 408: 331: 307: 280: 13273:. In Hemaspaandra, Lane A.; Selman, Alan L. (eds.). 13102: 13061: 13059: 13057: 12880: 12856: 12832: 6483:
consists exactly of those problems that are in both
5142:
Important corollaries of Savitch's theorem are that
81:. In particular, most complexity classes consist of 13006: 11954:
Summary of relationships between complexity classes
9295:: a counting problem is formalized as the function 9181:solutions exist. For example, the decision problem 8943:is also helpful in investigating properties of the 7976:. A circuit family is an infinite list of circuits 6331:accepts with a probability at least 1/2. The class 5774:, and the space hierarchy theorem establishes that 4637:Reductions motivate the concept of a problem being 4406:that can be efficiently reduced to another problem 3720: 750: 12868: 12796: 12774: 12739: 12712:, allows a Turning machine to read inputs of size 12704: 12684: 12658: 11930: 11876: 11849: 11816: 11791: 11735: 11678: 11654: 11589: 11529: 11496: 11476: 11422: 11395: 11368: 11300: 11254: 11227: 11196: 11152: 11112: 11066: 11042: 10988: 10933: 10884: 10845: 10825: 10777: 10757: 10737: 10542: 10509: 10476: 10456: 10436: 10398: 10378: 10358: 10335: 10286: 10263: 10243: 10223: 10169: 10149: 10120: 9986: 9941: 9921: 9885: 9785: 9765: 9745: 9716: 9671: 9651: 9539: 9519: 9486: 9441: 9414: 9385: 9340: 9276: 9252: 9221: 9197: 8987: 8931: 8862: 8827: 8790: 8745: 8709: 8689: 8616: 8596: 8569: 8540: 8504: 8426: 8406: 8386: 8359: 8288: 8268: 8248: 8228: 8208: 8166: 8146: 8126: 8106: 8086: 8066: 8039: 7953: 7922: 7902: 7815: 7795: 7730: 7657: 7637: 7593: 7540: 7516: 7492: 7472: 7439: 7406: 7373: 7182: 7116: 7023: 6963: 6943: 6921: 6861: 6841: 6818: 6785: 6765: 6724: 6649: 6629: 6609: 6515:, then there must be no error for strings both in 6471: 6323: 6303: 6291:such that if a string is not in the language then 6283: 6187: 6136: 6116: 6094: 6043: 6023: 5999: 5979: 5959: 5939: 5754: 5600: 5446: 5407:{\displaystyle O(n^{k_{1}})\subseteq O(n^{k_{2}})} 5406: 5334: 5294: 5235: 5131: 5006: 4971: 4935: 4849: 4825: 4795: 4767: 4725: 4705: 4681: 4653: 4598: 4561: 4535: 4502: 4478: 4458: 4438: 4418: 4398: 4374: 4337: 4311: 4278: 4258: 4238: 4218: 4198: 4178: 4130: 4082: 4024: 3944: 3904: 3868: 3822: 3679: 3564: 3400: 3328: 3226: 3083: 3033: 2965: 2871: 2787: 2746: 2637: 2496: 2455: 2373: 2298: 2263: 2196: 2176: 2156: 2111: 2091: 2071: 2044: 2020: 2000: 1980: 1960: 1940: 1913: 1860: 1776: 1644: 1614:is the set of all problems that are decided by an 1606: 1546: 1516:is the set of all problems that are decided by an 1508: 1448: 1418:is the set of all problems that are decided by an 1410: 1353: 1323:is the set of all problems that are decided by an 1315: 1218: 1198: 1178: 1143:{\displaystyle s_{M}:\mathbb {N} \to \mathbb {N} } 1142: 1099: 1044: 1024: 1004: 969:{\displaystyle t_{M}:\mathbb {N} \to \mathbb {N} } 968: 925: 873: 708: 681:algorithm can be represented as a Turing machine. 623:The most commonly used computational model is the 542: 511: 448: 418: 374: 317: 286: 27:Set of problems in computational complexity theory 13054: 13018: 11600: 10553: 10113: 10018: 9569: 9042:from an input node to the output node. The class 8631: 7048:with polynomial space resources, and vice versa. 6661: 6558:A number of complexity classes are defined using 4621:, and can vary based on resource bounds, such as 2798:. It is not known whether this is proper, but if 1882:increases relatively slowly with the input size. 526:would answer "yes" to. In the primality example, 13986: 13475:(2nd ed.). USA: Thomson Course Technology. 13173:Electronic Colloquim on Computational Complexity 11931:{\displaystyle \{0,1\}^{*}/\Pi _{\text{ACCEPT}}} 11792:{\displaystyle x\in \Pi _{\text{REJECT}},M(x)=0} 11736:{\displaystyle x\in \Pi _{\text{ACCEPT}},M(x)=1} 11477:{\displaystyle \{0,1\}^{*}/\Pi _{\text{ACCEPT}}} 9422:is the number of solutions. For example, in the 8932:{\displaystyle {\mathsf {P}}\neq {\mathsf {NP}}} 7823:of the circuit is represented mathematically as 7605:in which edges represent wires (which carry the 6978: 6876: 2497:{\displaystyle {\mathsf {P}}\neq {\mathsf {NP}}} 2456:{\displaystyle {\mathsf {P}}\neq {\mathsf {NP}}} 1697:is the class of problems that are solvable by a 1685:is the class of problems that are solvable by a 649: 628: 58:". The two most commonly analyzed resources are 13224:"Complexity classes having to do with counting" 12958: 11941:Formulating many basic complexity classes like 9151:. These are explained in greater detail below. 6491:. Intuitively, this follows from the fact that 6198: 4025:{\displaystyle O(n^{3})\circ O(n^{2})=O(n^{6})} 2401:, then it follows that nondeterminism provides 13502:"Lecture 22: Quantum computational complexity" 13251:Computer Science 522: Computational Complexity 9922:{\displaystyle p:\mathbb {N} \to \mathbb {N} } 8999:and other complexity classes is available at " 8995:. A full description of the relations between 8746:{\displaystyle t:\mathbb {N} \to \mathbb {N} } 8541:{\displaystyle f:\mathbb {N} \to \mathbb {N} } 7903:{\displaystyle b=f_{C}(x_{1},x_{2},...,x_{n})} 7199:(multiprover interactive polynomial time) and 5785: 107:) and using other models of computation (e.g. 13591: 13399:CSE431: Introduction to Theory of Computation 10106: 10025: 9886:{\displaystyle f:\{0,1\}^{*}\to \mathbb {N} } 9652:{\displaystyle f:\{0,1\}^{*}\to \mathbb {N} } 9341:{\displaystyle f:\{0,1\}^{*}\to \mathbb {N} } 7055:produces another important complexity class: 5895:These are explained in greater detail below. 5747: 5701: 5669: 5650: 5593: 5540: 5511: 5492: 3713:, and is believed to be a strict superset of 237:resources. For example, the complexity class 12747:, there will invariably reach a point where 11904: 11891: 11666:if there exists a polynomial-time algorithm 11578: 11565: 11450: 11437: 11357: 11344: 11031: 11018: 10977: 10964: 10873: 10860: 10814: 10801: 10726: 10713: 10049: 10036: 9975: 9962: 9866: 9853: 9813:if there exists a polynomial-time checkable 9705: 9692: 9632: 9619: 9475: 9462: 9374: 9361: 9321: 9308: 7731:{\displaystyle f_{C}:\{0,1\}^{n}\to \{0,1\}} 7725: 7713: 7701: 7688: 6547: 5295:{\displaystyle {\mathsf {DTIME}}(n^{k_{2}})} 5236:{\displaystyle {\mathsf {DTIME}}(n^{k_{1}})} 3817: 3786: 2233: 2220: 2145: 2132: 492:—the kinds of problems that can be posed as 369: 342: 267:is just a question that can be solved by an 13195:Computational Complexity: A Modern Approach 11050:is the set of all inputs that are rejected. 10996:is the set of all inputs that are accepted. 10853:by restricting the input to some subset of 10231:are computed. Formally, a function problem 9753:equals the number of accepting branches in 8894:. For example, if there is any language in 7556:An alternative model of computation to the 6374:that can be run quickly on real computers. 6188:{\displaystyle {\text{Pr}}\geq 1-\epsilon } 6095:{\displaystyle {\text{Pr}}\geq 1-\epsilon } 2817: 2467:employed today rely on the assumption that 1229: 13598: 13584: 13183: 13084: 13048: 13036: 13000: 12976: 12814: 10558:An important function complexity class is 10464:. This is just another way of saying that 9829:such certificates exist. In this context, 9130: 8798:. It follows directly from this fact that 5790:While deterministic and non-deterministic 4466:is polynomial-time reducible to a problem 2321: 1656: 781:branch of its computation. Similarly, the 432:is equivalent to saying that the language 13544: 13469:Introduction to the Theory of Computation 13323: 13147: 13135: 13123: 11484:), which throughout this page is denoted 9915: 9907: 9879: 9645: 9334: 8988:{\displaystyle \Sigma _{2}^{\mathsf {P}}} 8855: 8845: 8820: 8739: 8731: 8534: 8526: 6464: 6454: 6444: 5898: 4864:Of particular importance is the class of 3778: 3626: 3511: 3419: 3282: 3180: 2696: 2587: 1885:An important characteristic of the class 1817: 1733: 1136: 1128: 962: 954: 352: 258: 13207:from the original on February 23, 2022. 13163: 12952: 12940: 12928: 12886: 12862: 12850: 9434: 9245: 9190: 7218: 7098:). However, it is the case that for all 6584: 6419:simply relaxes the error probability of 6202: 4899:Relationships between complexity classes 4871:problems—the most difficult problems in 1607:{\displaystyle {\mathsf {NSPACE}}(s(n))} 1509:{\displaystyle {\mathsf {DSPACE}}(s(n))} 760: 701: 659: 535: 467: 441: 411: 334: 310: 29: 13496: 13372: 13298: 13265: 13111: 13012: 12874: 12802: 8690:{\displaystyle {\mathsf {DTIME}}(t(n))} 8505:{\displaystyle (C_{0},C_{1},C_{2},...)} 8360:{\displaystyle (C_{0},C_{1},C_{2},...)} 8040:{\displaystyle (C_{0},C_{1},C_{2},...)} 7205:(quantum interactive polynomial time). 7024:{\displaystyle \Pr\leq {\tfrac {1}{3}}} 6922:{\displaystyle \Pr\geq {\tfrac {2}{3}}} 2507: 2422:that proof (that is, the problem is in 1411:{\displaystyle {\mathsf {NTIME}}(t(n))} 1316:{\displaystyle {\mathsf {DTIME}}(t(n))} 677:); this means that it is believed that 598: 594:(see section "Other types of problems") 14: 13987: 13605: 13462: 13458:from the original on January 21, 2022. 13412:from the original on November 29, 2021 13319:from the original on November 2, 2021. 13301:"Guest Column: The Third P =? NP Poll" 13150:, p. 266 (11–12 in provided pdf). 12988: 12913: 12898: 12838: 12826: 11978:with a dark line connecting them. If 11850:{\displaystyle L=\Pi _{\text{ACCEPT}}} 11530:{\displaystyle \Pi _{\text{ACCEPT}}=L} 10738:{\displaystyle L\subseteq \{0,1\}^{*}} 10661:is the function problem equivalent of 10651:is the function problem equivalent of 9065: 8979: 8924: 8921: 8911: 8809: 8664: 8661: 8658: 8655: 8652: 7665:input variables is represented by the 7166: 7163: 7144: 7141: 6811: 6808: 5876:A number of classes are defined using 5852:A number of classes are defined using 5828:A number of classes are defined using 5798:A number of classes are defined using 5694: 5691: 5688: 5685: 5682: 5679: 5643: 5640: 5637: 5634: 5631: 5628: 5533: 5530: 5527: 5524: 5521: 5485: 5482: 5479: 5476: 5473: 5264: 5261: 5258: 5255: 5252: 5205: 5202: 5199: 5196: 5193: 5090: 5087: 5084: 5081: 5078: 5075: 5041: 5038: 5035: 5032: 5029: 5026: 4857:is as hard as the hardest problems in 3812: 3649: 3646: 3643: 3640: 3637: 3634: 3606: 3603: 3600: 3597: 3594: 3591: 3588: 3585: 3582: 3534: 3531: 3528: 3525: 3522: 3519: 3491: 3488: 3485: 3482: 3479: 3476: 3473: 3470: 3393: 3390: 3387: 3384: 3381: 3378: 3368: 3305: 3302: 3299: 3296: 3293: 3290: 3262: 3259: 3256: 3253: 3250: 3247: 3244: 3203: 3200: 3197: 3194: 3191: 3188: 3160: 3157: 3154: 3151: 3148: 3145: 3076: 3066: 3063: 3053: 3011: 3008: 3005: 3002: 2999: 2996: 2986: 2983: 2943: 2940: 2937: 2934: 2931: 2928: 2918: 2716: 2713: 2710: 2707: 2704: 2676: 2673: 2670: 2667: 2664: 2661: 2658: 2655: 2607: 2604: 2601: 2598: 2595: 2567: 2564: 2561: 2558: 2555: 2552: 2549: 2489: 2486: 2476: 2448: 2445: 2435: 2366: 2363: 2353: 1837: 1834: 1831: 1828: 1825: 1797: 1794: 1753: 1750: 1747: 1744: 1741: 1713: 1701:in polynomial time. Or more formally, 1652:space nondeterministic Turing machine. 1581: 1578: 1575: 1572: 1569: 1566: 1483: 1480: 1477: 1474: 1471: 1468: 1385: 1382: 1379: 1376: 1373: 1290: 1287: 1284: 1281: 1278: 866: 863: 860: 857: 854: 851: 848: 838: 732:places the additional constraint over 13579: 13238: 13221: 13065: 13024: 9929:and a polynomial-time Turing machine 9817:to a given problem instance—that is, 9599:is thus formally defined as follows: 8808: 7796:{\displaystyle x_{1},x_{2},...,x_{n}} 5165: 3730:Complexity classes have a variety of 3094: 2264:{\displaystyle c\in \{0,1\}^{p(|w|)}} 1456:time nondeterministic Turing machine. 821:(or more accurately, for problems in 720:accepts. A Turing machine is said to 484:(alternatively, 1 or 0) on any input. 183:in computer science concerns whether 13424: 13126:, p. 255 (2–3 in provided pdf). 13099:, p. 689 (510 in provided PDF). 13096: 11877:{\displaystyle \Pi _{\text{REJECT}}} 11423:{\displaystyle \Pi _{\text{REJECT}}} 11396:{\displaystyle \Pi _{\text{ACCEPT}}} 11255:{\displaystyle \Pi _{\text{REJECT}}} 11228:{\displaystyle \Pi _{\text{ACCEPT}}} 10181: 9949:(the verifier), such that for every 9893:such that there exists a polynomial 9494:(a graph represented as a string of 9154: 9069: 4903: 4083:{\displaystyle O(n^{6})>O(n^{3})} 3912:time. Both of these problems are in 1240: 1186:is the maximum number of cells that 1012:is the maximum number of steps that 463: 13520:from the original on June 18, 2022. 13389: 13261:from the original on April 3, 2021. 13179:from the original on June 17, 2020. 12964: 10686: 9442:{\displaystyle \#{\texttt {CYCLE}}} 9253:{\displaystyle \#{\texttt {CYCLE}}} 7208: 7051:A modification of the protocol for 6819:{\displaystyle L\in {\mathsf {IP}}} 6708:. As noted in the section above on 4186:to base-2 addition by transforming 1554:space deterministic Turing machine. 611:, complexity classes deal with the 426:problem is in the complexity class 24: 13525: 13383:10.1016/b978-0-444-88071-0.50007-2 13275:Complexity Theory Retrospective II 13234:from the original on May 21, 2022. 13138:, p. 257 (4 in provided pdf). 11919: 11865: 11838: 11759: 11703: 11640: 11627: 11512: 11465: 11411: 11384: 11332: 11319: 11295: 11283: 11270: 11243: 11216: 11185: 11172: 11141: 11128: 11098: 11085: 11006: 10952: 10919: 10906: 10531: 10444:, the algorithm produces one such 10324: 10311: 10281: 9527:is the number of simple cycles in 9429: 9240: 8969: 7535: 7355: 7285: 6997: after interacting with  6895: after interacting with  4879:can be polynomial-time reduced to 4733:allows us to solve any problem in 4669:can be polynomial-time reduced to 4641:for a complexity class. A problem 4524: 4300: 1361:time deterministic Turing machine. 792: 25: 14021: 13960:Probabilistically checkable proof 13550:"Computational Complexity Theory" 13368:from the original on May 6, 2021. 13175:. Weizmann Institute of Science. 9198:{\displaystyle {\texttt {CYCLE}}} 9117:, which are of key importance in 8753:, then it has circuit complexity 5947:. A probabilistic Turing machine 2403:no additional computational power 709:{\displaystyle {\texttt {PRIME}}} 543:{\displaystyle {\texttt {PRIME}}} 449:{\displaystyle {\texttt {PRIME}}} 419:{\displaystyle {\texttt {PRIME}}} 318:{\displaystyle {\texttt {PRIME}}} 12587: 12563: 12556: 12534: 12525: 12518: 12511: 12489: 12482: 12473: 12464: 12457: 12450: 12443: 12434: 12412: 12405: 12398: 12389: 12380: 12373: 12366: 12359: 12309: 12302: 12293: 12284: 12277: 12270: 12263: 12254: 12245: 12238: 12231: 12209: 12200: 12193: 12186: 12179: 12155: 12131: 12107: 12083: 12059: 12020: 12011: 11590:{\displaystyle s\in \{0,1\}^{*}} 10826:{\displaystyle w\in \{0,1\}^{*}} 10543:{\displaystyle x\in \Sigma ^{*}} 9987:{\displaystyle w\in \{0,1\}^{*}} 9717:{\displaystyle w\in \{0,1\}^{*}} 9487:{\displaystyle G\in \{0,1\}^{*}} 9386:{\displaystyle w\in \{0,1\}^{*}} 9260:(pronounced "sharp cycle") asks 9073: 5967:is said to recognize a language 4661:is hard for a class of problems 4536:{\displaystyle x\in \Sigma ^{*}} 4312:{\displaystyle x\in \Sigma ^{*}} 3721:Properties of complexity classes 3416:, but this has not been proven. 2344:problem. While it is known that 2157:{\displaystyle w\in \{0,1\}^{*}} 1068:? Or another kind of function? 751:Nondeterministic Turing machines 402:); for example, saying that the 14000:Computational complexity theory 13329:"On Promise Problems: A Survey" 13157: 12637:While a logarithmic runtime of 12034:Type 0 (Recursively enumerable) 9593:nondeterministic Turing machine 7968:(the formal representations of 6411:, which in turn is a subset of 5447:{\displaystyle k_{1}\leq k_{2}} 5335:{\displaystyle k_{1}\leq k_{2}} 4883:-complete problems, finding an 4750: 2843:While it is possible to define 1988:is in the language and rejects 1699:nondeterministic Turing machine 1265:, they are defined as follows: 1071: 757:Nondeterministic Turing machine 638:It is also possible to use the 609:computational complexity theory 476:has only two possible outputs, 40:computational complexity theory 13390:Lee, James R. (May 22, 2014). 13222:Arora, Sanjeev (Spring 2003). 13199:. Cambridge University Press. 12631: 11950:(statistical zero-knowledge). 11780: 11774: 11724: 11718: 11649: 11623: 11601:Relation to complexity classes 11107: 11081: 10928: 10902: 10504: 10498: 10425: 10413: 10215: 10144: 10138: 10095: 10083: 10072: 10068: 10060: 10056: 10010: 10004: 9911: 9875: 9740: 9734: 9641: 9514: 9508: 9449:problem, the input is a graph 9409: 9403: 9330: 8785: 8782: 8776: 8763: 8735: 8684: 8681: 8675: 8669: 8564: 8558: 8530: 8499: 8448: 8354: 8303: 8197: 8191: 8034: 7983: 7897: 7846: 7710: 7368: 7349: 7323: 7320: 7314: 7288: 7279: 7240: 7177: 7171: 7155: 7149: 7003: 6981: 6901: 6879: 6760: 6748: 6593:Interactive proof systems are 6170: 6156: 6077: 6063: 5742: 5739: 5733: 5727: 5715: 5709: 5664: 5658: 5588: 5585: 5579: 5573: 5554: 5548: 5506: 5500: 5401: 5381: 5372: 5352: 5289: 5269: 5230: 5210: 4995: 4989: 4960: 4953: 4930: 4924: 4587: 4581: 4363: 4357: 4125: 4112: 4077: 4064: 4055: 4042: 4019: 4006: 3997: 3984: 3975: 3962: 3939: 3926: 3899: 3886: 3863: 3857: 3793: 3674: 3654: 3559: 3539: 3339:While it is not known whether 3323: 3310: 3221: 3208: 3028: 3016: 2960: 2948: 2772:. It is further the case that 2741: 2721: 2632: 2612: 2293: 2281: 2256: 2252: 2244: 2240: 2052:is in the language. Formally: 1855: 1842: 1771: 1758: 1639: 1636: 1630: 1624: 1601: 1598: 1592: 1586: 1541: 1538: 1532: 1526: 1503: 1500: 1494: 1488: 1443: 1440: 1434: 1428: 1405: 1402: 1396: 1390: 1348: 1345: 1339: 1333: 1310: 1307: 1301: 1295: 1261:(for space complexity). Using 1173: 1167: 1132: 999: 993: 958: 897: 357: 73:, and a bounded resource like 13: 1: 13277:. Springer. pp. 81–106. 12789: 10271:over strings of an arbitrary 9173:a solution exists (as with a 9161:Counting problem (complexity) 8870:(for example, there are some 7738:; for example, on input bits 5800:probabilistic Turing machines 4145: 1032:takes on any input of length 650:Deterministic Turing machines 629:"Other models of computation" 208: 109:probabilistic Turing machines 14010:Theoretical computer science 13299:Gasarch, William I. (2019). 12775:{\displaystyle n>c\log n} 12740:{\displaystyle n<c\log n} 10570:deterministic Turing machine 10554:Important complexity classes 9606:is the set of all functions 9570:Important complexity classes 8632:Important complexity classes 7581:Formally, a Boolean circuit 7566:, a simplified model of the 7046:deterministic Turing machine 6662:Important complexity classes 6499:allow only one-sided error: 6199:Important complexity classes 5912:probabilistic Turing machine 4032:, which is a polynomial but 3802: 1687:deterministic Turing machine 1206:uses on any input of length 249:deterministic Turing machine 7: 12612: 10885:{\displaystyle \{0,1\}^{*}} 9119:quantum information science 8791:{\displaystyle O(t^{2}(n))} 8256:. In other words, a string 7132:. It is also the case that 6261:A slightly looser class is 5786:Other models of computation 4632: 4266:if there exists a function 3905:{\displaystyle O(n^{1000})} 3438:are the space analogues to 3113:are the space analogues to 2872:{\displaystyle \log n<n} 2828: 1667: 1557:The space complexity class 1459:The space complexity class 1107:is defined as the function 933:is defined as the function 175:(where ⊆ denotes the 54:"of related resource-based 10: 14026: 13976:List of complexity classes 12619:List of complexity classes 12223:Type 1 (Context Sensitive) 11054:The input to an algorithm 10690: 10437:{\displaystyle (x,y)\in R} 10185: 9573: 9348:such that for every input 9158: 8209:{\displaystyle C_{n}(w)=1} 7212: 6551: 5902: 5169: 4907: 4875:. Because all problems in 4833:is the hardest problem in 4623:polynomial-time reductions 4426:is no more difficult than 4149: 3725: 3423: 3098: 2832: 2821: 2788:{\displaystyle \subseteq } 2511: 2059:is the class of languages 1671: 1660: 1364:The time complexity class 1269:The time complexity class 1253:(for time complexity) and 1236:List of complexity classes 1233: 1075: 901: 754: 653: 13973: 13932: 13896: 13840: 13733: 13613: 13375:Algorithms and Complexity 12692:multiplied by a constant 12595: 12586: 12571: 12562: 12540: 12495: 12343: 12163: 12154: 12139: 12130: 12115: 12106: 12091: 12082: 12067: 12058: 12043: 12028: 12017: 12008: 11993: 11991: 10488:and the algorithm solves 10386:such that there exists a 10251:is defined as a relation 6725:{\displaystyle \epsilon } 6561:interactive proof systems 6548:Interactive proof systems 6000:{\displaystyle \epsilon } 5940:{\displaystyle \epsilon } 5830:interactive proof systems 5778:is strictly contained in 5770:is strictly contained in 5007:{\displaystyle f(n)>n} 4713:, since an algorithm for 4599:{\displaystyle p(x)\in Y} 4375:{\displaystyle f(x)\in Y} 3412:is strictly smaller than 2902:(sometimes lengthened to 2894:(sometimes lengthened to 398:(a concept borrowed from 243:is defined as the set of 113:interactive proof systems 85:that are solvable with a 18:Class (complexity theory) 13965:Interactive proof system 13403:University of Washington 13244:"Complexity of counting" 13230:. Princeton University. 12624: 12431: 12185: 10785:must act (correctly) on 10224:{\displaystyle f:A\to B} 9840:is the set of functions 9803:interactive proof system 9050:is defined similarly to 7034:An important feature of 6829:(Completeness) a string 6706:probabilistic algorithms 6576:approximation algorithms 6570:and yield insights into 6554:Interactive proof system 5880:, including the classes 5856:, including the classes 5832:, including the classes 5802:, including the classes 4972:{\displaystyle f(n)^{2}} 4131:{\displaystyle O(c^{n})} 3945:{\displaystyle O(n^{3})} 3359:. It is also known that 2818:Space complexity classes 2768:is a strict superset of 2760:is a strict superset of 2533:(sometimes shortened to 2525:(sometimes shortened to 2409:of computation provides 2389:is strictly larger than 1878:of solving a problem in 1230:Basic complexity classes 1179:{\displaystyle s_{M}(n)} 1005:{\displaystyle t_{M}(n)} 247:that can be solved by a 225:that can be solved by a 13266:Fortnow, Lance (1997). 12659:{\displaystyle c\log n} 11824:in the class is simply 11262:must be disjoint, i.e. 10287:{\displaystyle \Sigma } 9833:is defined as follows: 9773:'s computation tree on 9131:Other types of problems 9124:quantum Turing machines 8577:is the circuit size of 7576:non-uniform computation 7493:{\displaystyle \wedge } 7473:{\displaystyle x_{3}=0} 7440:{\displaystyle x_{2}=1} 7407:{\displaystyle x_{1}=0} 7117:{\displaystyle k\geq 2} 6248:The strictest class is 5987:with error probability 5878:quantum Turing machines 5614:space hierarchy theorem 5176:Space hierarchy theorem 3430:The complexity classes 3105:The complexity classes 2881:two-tape Turing machine 2322:The P versus NP problem 1657:Time complexity classes 1645:{\displaystyle O(s(n))} 1547:{\displaystyle O(s(n))} 1449:{\displaystyle O(t(n))} 1354:{\displaystyle O(t(n))} 271:. For example, "is the 213:Complexity classes are 14005:Measures of complexity 13919:Arithmetical hierarchy 13510:University of Waterloo 13309:University of Maryland 13085:Arora & Barak 2009 13049:Arora & Barak 2009 13037:Arora & Barak 2009 13001:Arora & Barak 2009 12977:Arora & Barak 2009 12815:Arora & Barak 2009 12776: 12741: 12706: 12686: 12685:{\displaystyle \log n} 12660: 11932: 11878: 11851: 11818: 11793: 11737: 11680: 11656: 11591: 11531: 11498: 11478: 11424: 11397: 11370: 11302: 11256: 11229: 11198: 11160:, which is called the 11154: 11114: 11074:for a promise problem 11068: 11044: 10990: 10935: 10886: 10847: 10827: 10779: 10759: 10739: 10544: 10511: 10478: 10458: 10438: 10400: 10380: 10360: 10337: 10288: 10265: 10245: 10225: 10171: 10151: 10122: 9988: 9943: 9923: 9887: 9787: 9767: 9747: 9718: 9673: 9653: 9552:statistical estimation 9541: 9521: 9488: 9443: 9416: 9387: 9342: 9278: 9254: 9223: 9199: 8989: 8933: 8864: 8829: 8792: 8747: 8711: 8691: 8618: 8598: 8571: 8542: 8506: 8428: 8414:) evaluates to 1 when 8408: 8388: 8361: 8290: 8270: 8250: 8230: 8210: 8168: 8148: 8128: 8108: 8088: 8068: 8041: 7955: 7924: 7904: 7817: 7797: 7732: 7659: 7639: 7603:directed acyclic graph 7595: 7553: 7542: 7518: 7494: 7474: 7441: 7408: 7375: 7184: 7118: 7082:can be generalized to 7025: 6965: 6945: 6923: 6863: 6843: 6820: 6787: 6767: 6726: 6710:randomized computation 6651: 6631: 6611: 6590: 6473: 6435:in the following way: 6325: 6305: 6285: 6212: 6189: 6138: 6118: 6096: 6045: 6025: 6001: 5981: 5961: 5941: 5905:Randomized computation 5899:Randomized computation 5756: 5602: 5459:time hierarchy theorem 5448: 5408: 5336: 5296: 5237: 5172:Time hierarchy theorem 5133: 5008: 4973: 4937: 4851: 4827: 4797: 4769: 4727: 4707: 4683: 4655: 4600: 4563: 4562:{\displaystyle x\in X} 4537: 4504: 4480: 4460: 4446:. Formally, a problem 4440: 4420: 4400: 4376: 4339: 4338:{\displaystyle x\in X} 4313: 4280: 4260: 4240: 4220: 4200: 4180: 4152:Reduction (complexity) 4132: 4084: 4026: 3946: 3906: 3870: 3824: 3681: 3566: 3420:EXPSPACE and NEXPSPACE 3402: 3330: 3228: 3085: 3035: 2967: 2873: 2789: 2748: 2639: 2498: 2457: 2375: 2300: 2299:{\displaystyle M(w,c)} 2265: 2198: 2178: 2158: 2113: 2093: 2073: 2046: 2022: 2002: 1982: 1962: 1942: 1915: 1862: 1778: 1646: 1608: 1548: 1510: 1450: 1412: 1355: 1317: 1220: 1200: 1180: 1144: 1101: 1046: 1026: 1006: 970: 927: 875: 766: 710: 665: 544: 513: 485: 450: 420: 376: 319: 288: 259:Computational problems 219:computational problems 52:computational problems 35: 13914:Grzegorczyk hierarchy 13909:Exponential hierarchy 13841:Considered infeasible 13268:"Counting Complexity" 12777: 12742: 12707: 12687: 12661: 12577:Type 2 (Context Free) 11933: 11879: 11852: 11819: 11794: 11738: 11681: 11657: 11592: 11532: 11499: 11479: 11425: 11398: 11371: 11303: 11257: 11230: 11199: 11155: 11115: 11069: 11045: 10991: 10936: 10887: 10848: 10828: 10780: 10760: 10740: 10545: 10512: 10479: 10459: 10439: 10401: 10381: 10361: 10338: 10289: 10266: 10246: 10226: 10172: 10152: 10123: 9989: 9944: 9924: 9888: 9788: 9768: 9748: 9719: 9674: 9654: 9595:'s computation tree. 9542: 9522: 9489: 9444: 9417: 9388: 9343: 9279: 9255: 9224: 9200: 8990: 8934: 8865: 8830: 8793: 8748: 8712: 8692: 8636:The complexity class 8619: 8599: 8597:{\displaystyle C_{n}} 8572: 8543: 8507: 8429: 8409: 8389: 8387:{\displaystyle C_{n}} 8362: 8291: 8271: 8251: 8231: 8211: 8169: 8149: 8129: 8114:if, for every string 8109: 8089: 8069: 8067:{\displaystyle C_{n}} 8042: 7956: 7954:{\displaystyle f_{C}} 7934:the Boolean function 7925: 7905: 7818: 7798: 7733: 7660: 7640: 7596: 7543: 7541:{\displaystyle \neg } 7519: 7517:{\displaystyle \vee } 7495: 7475: 7442: 7409: 7381:, with example input 7376: 7222: 7185: 7119: 7026: 6966: 6946: 6931:(Soundness) a string 6924: 6864: 6844: 6821: 6788: 6768: 6766:{\displaystyle (P,V)} 6727: 6652: 6632: 6612: 6588: 6474: 6372:randomized algorithms 6326: 6306: 6286: 6206: 6190: 6139: 6119: 6097: 6046: 6026: 6002: 5982: 5962: 5942: 5921:randomized algorithms 5757: 5603: 5449: 5409: 5337: 5297: 5238: 5134: 5009: 4974: 4938: 4852: 4828: 4798: 4770: 4741:is called the set of 4728: 4708: 4689:. Thus no problem in 4684: 4656: 4601: 4564: 4538: 4505: 4481: 4461: 4441: 4421: 4401: 4377: 4340: 4314: 4281: 4261: 4246:reduces to a problem 4241: 4221: 4201: 4181: 4133: 4085: 4027: 3947: 3907: 3871: 3825: 3682: 3567: 3403: 3351:famously showed that 3331: 3229: 3086: 3036: 2968: 2874: 2790: 2749: 2640: 2499: 2465:cryptographic schemes 2458: 2407:all possible branches 2376: 2301: 2266: 2199: 2179: 2159: 2114: 2094: 2074: 2047: 2023: 2003: 1983: 1963: 1943: 1916: 1863: 1779: 1647: 1609: 1549: 1511: 1451: 1413: 1356: 1318: 1221: 1201: 1181: 1145: 1102: 1047: 1027: 1007: 971: 928: 876: 764: 711: 663: 587:Optimization problems 545: 514: 471: 451: 421: 377: 320: 289: 265:computational problem 33: 13904:Polynomial hierarchy 13734:Suspected infeasible 13492:on February 7, 2022. 13255:Princeton University 12751: 12716: 12696: 12670: 12641: 11984:computability theory 11888: 11861: 11828: 11808: 11749: 11693: 11670: 11620: 11556: 11508: 11488: 11434: 11407: 11380: 11315: 11266: 11239: 11212: 11168: 11124: 11078: 11058: 11002: 10948: 10899: 10857: 10837: 10792: 10769: 10749: 10704: 10521: 10510:{\displaystyle f(x)} 10492: 10468: 10448: 10410: 10390: 10370: 10350: 10346:An algorithm solves 10301: 10278: 10255: 10235: 10203: 10161: 10150:{\displaystyle f(w)} 10132: 9998: 9953: 9933: 9897: 9844: 9777: 9757: 9746:{\displaystyle f(w)} 9728: 9683: 9663: 9610: 9587:. The connection to 9531: 9520:{\displaystyle f(G)} 9502: 9453: 9426: 9415:{\displaystyle f(w)} 9397: 9352: 9299: 9268: 9237: 9213: 9185: 9121:, are defined using 9001:Importance of P/poly 8965: 8945:polynomial hierarchy 8906: 8872:undecidable problems 8840: 8803: 8757: 8721: 8701: 8647: 8608: 8581: 8570:{\displaystyle f(n)} 8552: 8516: 8445: 8418: 8398: 8371: 8300: 8280: 8260: 8240: 8220: 8178: 8158: 8138: 8118: 8098: 8078: 8051: 7980: 7938: 7914: 7827: 7807: 7742: 7672: 7649: 7629: 7585: 7532: 7508: 7484: 7451: 7418: 7385: 7227: 7136: 7102: 7067:private random coins 6975: 6955: 6935: 6873: 6853: 6833: 6797: 6777: 6745: 6716: 6641: 6621: 6601: 6439: 6315: 6295: 6275: 6148: 6128: 6108: 6055: 6035: 6015: 5991: 5971: 5951: 5931: 5623: 5468: 5418: 5346: 5306: 5247: 5188: 5021: 4983: 4947: 4936:{\displaystyle f(n)} 4918: 4841: 4817: 4787: 4759: 4717: 4697: 4673: 4665:if every problem in 4645: 4627:log-space reductions 4575: 4547: 4514: 4494: 4490:computable function 4470: 4450: 4430: 4410: 4390: 4351: 4323: 4290: 4286:such that for every 4270: 4250: 4230: 4210: 4190: 4164: 4106: 4036: 3956: 3920: 3880: 3869:{\displaystyle O(n)} 3851: 3773: 3746:, or even under all 3577: 3465: 3363: 3239: 3140: 3048: 2978: 2913: 2851: 2779: 2650: 2544: 2508:EXPTIME and NEXPTIME 2471: 2430: 2348: 2275: 2211: 2188: 2168: 2123: 2103: 2083: 2063: 2036: 2012: 1992: 1972: 1952: 1932: 1905: 1789: 1708: 1618: 1561: 1520: 1463: 1422: 1368: 1327: 1273: 1210: 1190: 1154: 1111: 1091: 1066:exponential function 1062:logarithmic function 1036: 1016: 980: 937: 917: 833: 825:that are outside of 696: 675:Church–Turing thesis 599:Computational models 530: 503: 436: 406: 329: 305: 278: 71:model of computation 13933:Families of classes 13614:Considered feasible 13349:10.1007/11685654_12 11206:satisfy the promise 10366:if for every input 9556:statistical physics 9209:a particular graph 9066:Quantum computation 9060:parallel algorithms 8984: 8154:is in the language 7071:public random coins 6989: accepts  6887: accepts  6688:can also be called 6580:formal verification 6407:are all subsets of 6256:no error whatsoever 6164: rejects  6071: accepts  5915:, a variant of the 5862:and its subclasses 4179:{\displaystyle x+y} 3101:PSPACE (complexity) 718:tests for primality 644:computational model 605:computational model 552:tests for primality 13995:Complexity classes 13607:Complexity classes 13537:2019-08-27 at the 13532:The Complexity Zoo 13500:(April 11, 2006). 13167:(8 January 2017). 13051:, p. 341–342. 12829:, p. 48, 150. 12772: 12737: 12702: 12682: 12656: 11928: 11874: 11847: 11814: 11789: 11733: 11676: 11652: 11587: 11527: 11504:to emphasize that 11494: 11474: 11420: 11393: 11366: 11298: 11252: 11225: 11194: 11150: 11110: 11064: 11040: 10986: 10931: 10882: 10843: 10823: 10775: 10755: 10735: 10540: 10507: 10474: 10454: 10434: 10396: 10376: 10356: 10333: 10284: 10261: 10241: 10221: 10167: 10147: 10128:. In other words, 10118: 9984: 9939: 9919: 9883: 9783: 9763: 9743: 9714: 9679:such that for all 9669: 9649: 9537: 9517: 9484: 9439: 9412: 9383: 9338: 9274: 9250: 9219: 9195: 9085:. You can help by 9018:Two subclasses of 8985: 8968: 8947:. For example, if 8929: 8860: 8825: 8812: 8788: 8743: 8707: 8687: 8614: 8594: 8567: 8538: 8502: 8424: 8404: 8384: 8357: 8286: 8266: 8246: 8226: 8206: 8164: 8144: 8124: 8104: 8084: 8074:is a circuit with 8064: 8037: 7951: 7920: 7900: 7813: 7793: 7728: 7655: 7635: 7591: 7554: 7538: 7514: 7490: 7470: 7437: 7404: 7371: 7215:Circuit complexity 7180: 7114: 7038:is that it equals 7021: 7019: 6961: 6941: 6919: 6917: 6859: 6839: 6816: 6783: 6763: 6722: 6695:It turns out that 6647: 6627: 6607: 6591: 6469: 6321: 6301: 6281: 6213: 6209:quantum complexity 6185: 6134: 6114: 6092: 6041: 6021: 5997: 5977: 5957: 5937: 5752: 5598: 5444: 5404: 5332: 5292: 5233: 5184:, it follows that 5166:Hierarchy theorems 5129: 5004: 4969: 4933: 4847: 4823: 4813:. This means that 4793: 4765: 4723: 4703: 4679: 4651: 4596: 4559: 4533: 4510:such that for all 4500: 4486:if there exists a 4476: 4456: 4436: 4416: 4396: 4372: 4335: 4309: 4276: 4256: 4236: 4216: 4196: 4176: 4128: 4080: 4022: 3942: 3902: 3866: 3820: 3748:Boolean operations 3677: 3631: 3562: 3516: 3398: 3349:Savitch's theorem 3326: 3287: 3224: 3185: 3095:PSPACE and NPSPACE 3081: 3031: 2963: 2869: 2785: 2744: 2701: 2635: 2592: 2494: 2453: 2371: 2296: 2261: 2207:there exists some 2194: 2174: 2154: 2119:such that for all 2109: 2089: 2069: 2042: 2018: 1998: 1978: 1958: 1938: 1924:a polynomial-size 1911: 1897:if there exists a 1858: 1822: 1774: 1738: 1642: 1604: 1544: 1506: 1446: 1408: 1351: 1313: 1216: 1196: 1176: 1140: 1097: 1042: 1022: 1002: 966: 923: 871: 767: 706: 666: 540: 509: 486: 446: 416: 372: 315: 284: 36: 13982: 13981: 13924:Boolean hierarchy 13897:Class hierarchies 13358:978-3-540-32881-0 13294:on June 18, 2022. 13214:978-0-521-42426-4 12705:{\displaystyle c} 12610: 12609: 12606: 12605: 12582: 12581: 12551: 12550: 12506: 12505: 12429: 12428: 12354: 12353: 12339: 12338: 12326: 12325: 12228: 12227: 12174: 12173: 12150: 12149: 12126: 12125: 12102: 12101: 12078: 12077: 12054: 12053: 12039: 12038: 12004: 12003: 11925: 11871: 11844: 11817:{\displaystyle L} 11765: 11709: 11679:{\displaystyle M} 11646: 11633: 11518: 11497:{\displaystyle L} 11471: 11430:implicitly being 11417: 11390: 11338: 11325: 11289: 11276: 11249: 11222: 11208:. By definition, 11191: 11178: 11147: 11134: 11104: 11091: 11067:{\displaystyle M} 11012: 10958: 10925: 10912: 10846:{\displaystyle M} 10778:{\displaystyle L} 10758:{\displaystyle M} 10477:{\displaystyle f} 10457:{\displaystyle y} 10399:{\displaystyle y} 10379:{\displaystyle x} 10359:{\displaystyle f} 10264:{\displaystyle R} 10244:{\displaystyle f} 10194:function problems 10182:Function problems 10170:{\displaystyle w} 9942:{\displaystyle V} 9786:{\displaystyle w} 9766:{\displaystyle M} 9672:{\displaystyle M} 9540:{\displaystyle G} 9436: 9277:{\displaystyle G} 9247: 9222:{\displaystyle G} 9192: 9155:Counting problems 9145:function problems 9141:counting problems 9137:decision problems 9103: 9102: 8857: 8847: 8822: 8710:{\displaystyle t} 8617:{\displaystyle f} 8427:{\displaystyle w} 8407:{\displaystyle w} 8289:{\displaystyle n} 8269:{\displaystyle w} 8249:{\displaystyle w} 8236:is the length of 8229:{\displaystyle n} 8167:{\displaystyle L} 8147:{\displaystyle w} 8127:{\displaystyle w} 8107:{\displaystyle L} 8087:{\displaystyle n} 7970:decision problems 7923:{\displaystyle C} 7816:{\displaystyle b} 7803:, the output bit 7658:{\displaystyle n} 7638:{\displaystyle C} 7594:{\displaystyle C} 7094:defined above is 7018: 6998: 6990: 6964:{\displaystyle L} 6944:{\displaystyle w} 6916: 6896: 6888: 6862:{\displaystyle L} 6842:{\displaystyle w} 6786:{\displaystyle V} 6650:{\displaystyle P} 6630:{\displaystyle V} 6610:{\displaystyle P} 6595:abstract machines 6466: 6456: 6446: 6356:yields the class 6324:{\displaystyle M} 6304:{\displaystyle M} 6284:{\displaystyle M} 6165: 6154: 6137:{\displaystyle L} 6117:{\displaystyle w} 6072: 6061: 6044:{\displaystyle L} 6024:{\displaystyle w} 5980:{\displaystyle L} 5960:{\displaystyle M} 5180:By definition of 4910:Savitch's theorem 4904:Savitch's theorem 4850:{\displaystyle X} 4826:{\displaystyle X} 4796:{\displaystyle X} 4768:{\displaystyle X} 4726:{\displaystyle X} 4706:{\displaystyle X} 4682:{\displaystyle X} 4654:{\displaystyle X} 4503:{\displaystyle p} 4479:{\displaystyle Y} 4459:{\displaystyle X} 4439:{\displaystyle Y} 4419:{\displaystyle Y} 4399:{\displaystyle X} 4279:{\displaystyle f} 4259:{\displaystyle Y} 4239:{\displaystyle X} 4219:{\displaystyle y} 4199:{\displaystyle x} 3805: 3780: 3691:Savitch's theorem 3614: 3499: 3270: 3168: 3044:It is known that 2684: 2575: 2197:{\displaystyle L} 2177:{\displaystyle w} 2112:{\displaystyle p} 2099:and a polynomial 2092:{\displaystyle M} 2072:{\displaystyle L} 2045:{\displaystyle w} 2021:{\displaystyle w} 2001:{\displaystyle w} 1981:{\displaystyle w} 1961:{\displaystyle w} 1941:{\displaystyle c} 1914:{\displaystyle w} 1805: 1721: 1241:Basic definitions 1219:{\displaystyle n} 1199:{\displaystyle M} 1100:{\displaystyle M} 1045:{\displaystyle n} 1025:{\displaystyle M} 926:{\displaystyle M} 703: 575:Counting problems 563:Function problems 537: 512:{\displaystyle n} 490:decision problems 464:Decision problems 443: 413: 367: 336: 312: 287:{\displaystyle n} 245:decision problems 223:decision problems 121:quantum computers 105:function problems 101:counting problems 83:decision problems 16:(Redirected from 14017: 13600: 13593: 13586: 13577: 13576: 13566:David S. Johnson 13557: 13552:. Archived from 13521: 13519: 13506: 13493: 13491: 13485:. Archived from 13474: 13459: 13457: 13436: 13421: 13419: 13417: 13411: 13396: 13386: 13369: 13367: 13342: 13333: 13320: 13318: 13305: 13295: 13293: 13287:. Archived from 13272: 13262: 13248: 13235: 13218: 13198: 13180: 13151: 13145: 13139: 13133: 13127: 13121: 13115: 13109: 13100: 13094: 13088: 13082: 13069: 13063: 13052: 13046: 13040: 13034: 13028: 13022: 13016: 13010: 13004: 12998: 12992: 12986: 12980: 12974: 12968: 12962: 12956: 12950: 12944: 12938: 12932: 12926: 12917: 12911: 12902: 12896: 12890: 12884: 12878: 12872: 12866: 12860: 12854: 12848: 12842: 12836: 12830: 12824: 12818: 12812: 12806: 12800: 12783: 12781: 12779: 12778: 12773: 12746: 12744: 12743: 12738: 12711: 12709: 12708: 12703: 12691: 12689: 12688: 12683: 12665: 12663: 12662: 12657: 12635: 12601:Type 3 (Regular) 12597: 12591: 12573: 12567: 12560: 12542: 12538: 12529: 12522: 12515: 12497: 12493: 12486: 12477: 12468: 12461: 12454: 12447: 12438: 12420: 12416: 12409: 12402: 12393: 12384: 12377: 12370: 12363: 12345: 12330: 12317: 12313: 12306: 12297: 12288: 12281: 12274: 12267: 12258: 12249: 12242: 12235: 12219: 12213: 12204: 12197: 12190: 12183: 12165: 12159: 12141: 12135: 12117: 12111: 12093: 12087: 12069: 12063: 12045: 12030: 12024: 12015: 11999:Decision Problem 11995: 11989: 11937: 11935: 11934: 11929: 11927: 11926: 11923: 11917: 11912: 11911: 11883: 11881: 11880: 11875: 11873: 11872: 11869: 11856: 11854: 11853: 11848: 11846: 11845: 11842: 11823: 11821: 11820: 11815: 11798: 11796: 11795: 11790: 11767: 11766: 11763: 11742: 11740: 11739: 11734: 11711: 11710: 11707: 11685: 11683: 11682: 11677: 11661: 11659: 11658: 11653: 11648: 11647: 11644: 11635: 11634: 11631: 11596: 11594: 11593: 11588: 11586: 11585: 11536: 11534: 11533: 11528: 11520: 11519: 11516: 11503: 11501: 11500: 11495: 11483: 11481: 11480: 11475: 11473: 11472: 11469: 11463: 11458: 11457: 11429: 11427: 11426: 11421: 11419: 11418: 11415: 11402: 11400: 11399: 11394: 11392: 11391: 11388: 11375: 11373: 11372: 11367: 11365: 11364: 11340: 11339: 11336: 11327: 11326: 11323: 11307: 11305: 11304: 11299: 11291: 11290: 11287: 11278: 11277: 11274: 11261: 11259: 11258: 11253: 11251: 11250: 11247: 11234: 11232: 11231: 11226: 11224: 11223: 11220: 11203: 11201: 11200: 11195: 11193: 11192: 11189: 11180: 11179: 11176: 11159: 11157: 11156: 11151: 11149: 11148: 11145: 11136: 11135: 11132: 11119: 11117: 11116: 11111: 11106: 11105: 11102: 11093: 11092: 11089: 11073: 11071: 11070: 11065: 11049: 11047: 11046: 11041: 11039: 11038: 11014: 11013: 11010: 10995: 10993: 10992: 10987: 10985: 10984: 10960: 10959: 10956: 10940: 10938: 10937: 10932: 10927: 10926: 10923: 10914: 10913: 10910: 10891: 10889: 10888: 10883: 10881: 10880: 10852: 10850: 10849: 10844: 10832: 10830: 10829: 10824: 10822: 10821: 10784: 10782: 10781: 10776: 10764: 10762: 10761: 10756: 10744: 10742: 10741: 10736: 10734: 10733: 10698:Promise problems 10687:Promise problems 10549: 10547: 10546: 10541: 10539: 10538: 10516: 10514: 10513: 10508: 10483: 10481: 10480: 10475: 10463: 10461: 10460: 10455: 10443: 10441: 10440: 10435: 10405: 10403: 10402: 10397: 10385: 10383: 10382: 10377: 10365: 10363: 10362: 10357: 10342: 10340: 10339: 10334: 10332: 10331: 10319: 10318: 10293: 10291: 10290: 10285: 10270: 10268: 10267: 10262: 10250: 10248: 10247: 10242: 10230: 10228: 10227: 10222: 10188:Function problem 10176: 10174: 10173: 10168: 10156: 10154: 10153: 10148: 10127: 10125: 10124: 10119: 10117: 10116: 10110: 10109: 10076: 10075: 10071: 10063: 10029: 10028: 10022: 10021: 9993: 9991: 9990: 9985: 9983: 9982: 9948: 9946: 9945: 9940: 9928: 9926: 9925: 9920: 9918: 9910: 9892: 9890: 9889: 9884: 9882: 9874: 9873: 9792: 9790: 9789: 9784: 9772: 9770: 9769: 9764: 9752: 9750: 9749: 9744: 9723: 9721: 9720: 9715: 9713: 9712: 9678: 9676: 9675: 9670: 9658: 9656: 9655: 9650: 9648: 9640: 9639: 9546: 9544: 9543: 9538: 9526: 9524: 9523: 9518: 9493: 9491: 9490: 9485: 9483: 9482: 9448: 9446: 9445: 9440: 9438: 9437: 9421: 9419: 9418: 9413: 9392: 9390: 9389: 9384: 9382: 9381: 9347: 9345: 9344: 9339: 9337: 9329: 9328: 9289:formal languages 9283: 9281: 9280: 9275: 9259: 9257: 9256: 9251: 9249: 9248: 9228: 9226: 9225: 9220: 9204: 9202: 9201: 9196: 9194: 9193: 9175:decision problem 9167:counting problem 9149:promise problems 9098: 9095: 9077: 9070: 8994: 8992: 8991: 8986: 8983: 8982: 8976: 8938: 8936: 8935: 8930: 8928: 8927: 8915: 8914: 8869: 8867: 8866: 8861: 8859: 8858: 8849: 8848: 8834: 8832: 8831: 8826: 8824: 8823: 8814: 8813: 8797: 8795: 8794: 8789: 8775: 8774: 8752: 8750: 8749: 8744: 8742: 8734: 8716: 8714: 8713: 8708: 8696: 8694: 8693: 8688: 8668: 8667: 8623: 8621: 8620: 8615: 8603: 8601: 8600: 8595: 8593: 8592: 8576: 8574: 8573: 8568: 8547: 8545: 8544: 8539: 8537: 8529: 8512:is the function 8511: 8509: 8508: 8503: 8486: 8485: 8473: 8472: 8460: 8459: 8433: 8431: 8430: 8425: 8413: 8411: 8410: 8405: 8393: 8391: 8390: 8385: 8383: 8382: 8366: 8364: 8363: 8358: 8341: 8340: 8328: 8327: 8315: 8314: 8295: 8293: 8292: 8287: 8275: 8273: 8272: 8267: 8255: 8253: 8252: 8247: 8235: 8233: 8232: 8227: 8215: 8213: 8212: 8207: 8190: 8189: 8173: 8171: 8170: 8165: 8153: 8151: 8150: 8145: 8133: 8131: 8130: 8125: 8113: 8111: 8110: 8105: 8093: 8091: 8090: 8085: 8073: 8071: 8070: 8065: 8063: 8062: 8046: 8044: 8043: 8038: 8021: 8020: 8008: 8007: 7995: 7994: 7960: 7958: 7957: 7952: 7950: 7949: 7929: 7927: 7926: 7921: 7909: 7907: 7906: 7901: 7896: 7895: 7871: 7870: 7858: 7857: 7845: 7844: 7822: 7820: 7819: 7814: 7802: 7800: 7799: 7794: 7792: 7791: 7767: 7766: 7754: 7753: 7737: 7735: 7734: 7729: 7709: 7708: 7684: 7683: 7667:Boolean function 7664: 7662: 7661: 7656: 7644: 7642: 7641: 7636: 7600: 7598: 7597: 7592: 7568:digital circuits 7547: 7545: 7544: 7539: 7523: 7521: 7520: 7515: 7499: 7497: 7496: 7491: 7479: 7477: 7476: 7471: 7463: 7462: 7446: 7444: 7443: 7438: 7430: 7429: 7413: 7411: 7410: 7405: 7397: 7396: 7380: 7378: 7377: 7372: 7367: 7366: 7348: 7347: 7335: 7334: 7313: 7312: 7300: 7299: 7278: 7277: 7265: 7264: 7252: 7251: 7239: 7238: 7209:Boolean circuits 7189: 7187: 7186: 7181: 7170: 7169: 7148: 7147: 7123: 7121: 7120: 7115: 7030: 7028: 7027: 7022: 7020: 7011: 6999: 6996: 6991: 6988: 6970: 6968: 6967: 6962: 6950: 6948: 6947: 6942: 6928: 6926: 6925: 6920: 6918: 6909: 6897: 6894: 6889: 6886: 6868: 6866: 6865: 6860: 6848: 6846: 6845: 6840: 6825: 6823: 6822: 6817: 6815: 6814: 6792: 6790: 6789: 6784: 6772: 6770: 6769: 6764: 6731: 6729: 6728: 6723: 6656: 6654: 6653: 6648: 6636: 6634: 6633: 6628: 6616: 6614: 6613: 6608: 6478: 6476: 6475: 6470: 6468: 6467: 6458: 6457: 6448: 6447: 6330: 6328: 6327: 6322: 6310: 6308: 6307: 6302: 6290: 6288: 6287: 6282: 6194: 6192: 6191: 6186: 6166: 6163: 6155: 6152: 6143: 6141: 6140: 6135: 6123: 6121: 6120: 6115: 6101: 6099: 6098: 6093: 6073: 6070: 6062: 6059: 6050: 6048: 6047: 6042: 6030: 6028: 6027: 6022: 6006: 6004: 6003: 5998: 5986: 5984: 5983: 5978: 5966: 5964: 5963: 5958: 5946: 5944: 5943: 5938: 5854:Boolean circuits 5761: 5759: 5758: 5753: 5751: 5750: 5705: 5704: 5698: 5697: 5673: 5672: 5654: 5653: 5647: 5646: 5607: 5605: 5604: 5599: 5597: 5596: 5569: 5568: 5544: 5543: 5537: 5536: 5515: 5514: 5496: 5495: 5489: 5488: 5453: 5451: 5450: 5445: 5443: 5442: 5430: 5429: 5413: 5411: 5410: 5405: 5400: 5399: 5398: 5397: 5371: 5370: 5369: 5368: 5341: 5339: 5338: 5333: 5331: 5330: 5318: 5317: 5301: 5299: 5298: 5293: 5288: 5287: 5286: 5285: 5268: 5267: 5243:is contained in 5242: 5240: 5239: 5234: 5229: 5228: 5227: 5226: 5209: 5208: 5138: 5136: 5135: 5130: 5125: 5121: 5120: 5119: 5114: 5094: 5093: 5069: 5065: 5064: 5045: 5044: 5013: 5011: 5010: 5005: 4978: 4976: 4975: 4970: 4968: 4967: 4942: 4940: 4939: 4934: 4856: 4854: 4853: 4848: 4832: 4830: 4829: 4824: 4802: 4800: 4799: 4794: 4774: 4772: 4771: 4766: 4732: 4730: 4729: 4724: 4712: 4710: 4709: 4704: 4688: 4686: 4685: 4680: 4660: 4658: 4657: 4652: 4619:Levin reductions 4605: 4603: 4602: 4597: 4568: 4566: 4565: 4560: 4542: 4540: 4539: 4534: 4532: 4531: 4509: 4507: 4506: 4501: 4485: 4483: 4482: 4477: 4465: 4463: 4462: 4457: 4445: 4443: 4442: 4437: 4425: 4423: 4422: 4417: 4405: 4403: 4402: 4397: 4381: 4379: 4378: 4373: 4344: 4342: 4341: 4336: 4318: 4316: 4315: 4310: 4308: 4307: 4285: 4283: 4282: 4277: 4265: 4263: 4262: 4257: 4245: 4243: 4242: 4237: 4225: 4223: 4222: 4217: 4205: 4203: 4202: 4197: 4185: 4183: 4182: 4177: 4142:is close to 1.) 4141: 4137: 4135: 4134: 4129: 4124: 4123: 4089: 4087: 4086: 4081: 4076: 4075: 4054: 4053: 4031: 4029: 4028: 4023: 4018: 4017: 3996: 3995: 3974: 3973: 3951: 3949: 3948: 3943: 3938: 3937: 3911: 3909: 3908: 3903: 3898: 3897: 3875: 3873: 3872: 3867: 3829: 3827: 3826: 3821: 3816: 3815: 3806: 3798: 3796: 3782: 3781: 3686: 3684: 3683: 3678: 3673: 3672: 3671: 3670: 3653: 3652: 3630: 3629: 3610: 3609: 3571: 3569: 3568: 3563: 3558: 3557: 3556: 3555: 3538: 3537: 3515: 3514: 3495: 3494: 3407: 3405: 3404: 3399: 3397: 3396: 3372: 3371: 3335: 3333: 3332: 3327: 3322: 3321: 3309: 3308: 3286: 3285: 3266: 3265: 3233: 3231: 3230: 3225: 3220: 3219: 3207: 3206: 3184: 3183: 3164: 3163: 3090: 3088: 3087: 3082: 3080: 3079: 3070: 3069: 3057: 3056: 3040: 3038: 3037: 3032: 3015: 3014: 2990: 2989: 2972: 2970: 2969: 2964: 2947: 2946: 2922: 2921: 2878: 2876: 2875: 2870: 2824:Space complexity 2794: 2792: 2791: 2786: 2753: 2751: 2750: 2745: 2740: 2739: 2738: 2737: 2720: 2719: 2700: 2699: 2680: 2679: 2644: 2642: 2641: 2636: 2631: 2630: 2629: 2628: 2611: 2610: 2591: 2590: 2571: 2570: 2503: 2501: 2500: 2495: 2493: 2492: 2480: 2479: 2462: 2460: 2459: 2454: 2452: 2451: 2439: 2438: 2380: 2378: 2377: 2372: 2370: 2369: 2357: 2356: 2305: 2303: 2302: 2297: 2270: 2268: 2267: 2262: 2260: 2259: 2255: 2247: 2203: 2201: 2200: 2195: 2183: 2181: 2180: 2175: 2163: 2161: 2160: 2155: 2153: 2152: 2118: 2116: 2115: 2110: 2098: 2096: 2095: 2090: 2078: 2076: 2075: 2070: 2051: 2049: 2048: 2043: 2027: 2025: 2024: 2019: 2007: 2005: 2004: 1999: 1987: 1985: 1984: 1979: 1967: 1965: 1964: 1959: 1947: 1945: 1944: 1939: 1920: 1918: 1917: 1912: 1867: 1865: 1864: 1859: 1854: 1853: 1841: 1840: 1821: 1820: 1801: 1800: 1783: 1781: 1780: 1775: 1770: 1769: 1757: 1756: 1737: 1736: 1717: 1716: 1651: 1649: 1648: 1643: 1613: 1611: 1610: 1605: 1585: 1584: 1553: 1551: 1550: 1545: 1515: 1513: 1512: 1507: 1487: 1486: 1455: 1453: 1452: 1447: 1417: 1415: 1414: 1409: 1389: 1388: 1360: 1358: 1357: 1352: 1322: 1320: 1319: 1314: 1294: 1293: 1225: 1223: 1222: 1217: 1205: 1203: 1202: 1197: 1185: 1183: 1182: 1177: 1166: 1165: 1149: 1147: 1146: 1141: 1139: 1131: 1123: 1122: 1106: 1104: 1103: 1098: 1084:space complexity 1078:Space complexity 1051: 1049: 1048: 1043: 1031: 1029: 1028: 1023: 1011: 1009: 1008: 1003: 992: 991: 975: 973: 972: 967: 965: 957: 949: 948: 932: 930: 929: 924: 880: 878: 877: 872: 870: 869: 842: 841: 783:space complexity 745:space complexity 715: 713: 712: 707: 705: 704: 592:Promise problems 549: 547: 546: 541: 539: 538: 518: 516: 515: 510: 494:yes–no questions 474:decision problem 455: 453: 452: 447: 445: 444: 425: 423: 422: 417: 415: 414: 396:formal languages 381: 379: 378: 373: 368: 365: 360: 355: 338: 337: 324: 322: 321: 316: 314: 313: 293: 291: 290: 285: 117:Boolean circuits 44:complexity class 21: 14025: 14024: 14020: 14019: 14018: 14016: 14015: 14014: 13985: 13984: 13983: 13978: 13969: 13928: 13892: 13836: 13830:PSPACE-complete 13729: 13609: 13604: 13539:Wayback Machine 13528: 13526:Further reading 13517: 13504: 13489: 13483: 13472: 13464:Sipser, Michael 13455: 13449: 13434: 13415: 13413: 13409: 13394: 13365: 13359: 13340: 13331: 13325:Goldreich, Oded 13316: 13303: 13291: 13285: 13270: 13246: 13242:(Spring 2006). 13215: 13165:Aaronson, Scott 13160: 13155: 13154: 13146: 13142: 13134: 13130: 13122: 13118: 13110: 13103: 13095: 13091: 13083: 13072: 13064: 13055: 13047: 13043: 13035: 13031: 13023: 13019: 13011: 13007: 12999: 12995: 12987: 12983: 12975: 12971: 12963: 12959: 12951: 12947: 12939: 12935: 12927: 12920: 12912: 12905: 12897: 12893: 12885: 12881: 12873: 12869: 12861: 12857: 12849: 12845: 12837: 12833: 12825: 12821: 12813: 12809: 12801: 12797: 12792: 12787: 12786: 12752: 12749: 12748: 12717: 12714: 12713: 12697: 12694: 12693: 12671: 12668: 12667: 12642: 12639: 12638: 12636: 12632: 12627: 12615: 11974:is shown below 11956: 11922: 11918: 11913: 11907: 11903: 11889: 11886: 11885: 11868: 11864: 11862: 11859: 11858: 11841: 11837: 11829: 11826: 11825: 11809: 11806: 11805: 11762: 11758: 11750: 11747: 11746: 11706: 11702: 11694: 11691: 11690: 11671: 11668: 11667: 11643: 11639: 11630: 11626: 11621: 11618: 11617: 11603: 11581: 11577: 11557: 11554: 11553: 11539:formal language 11515: 11511: 11509: 11506: 11505: 11489: 11486: 11485: 11468: 11464: 11459: 11453: 11449: 11435: 11432: 11431: 11414: 11410: 11408: 11405: 11404: 11387: 11383: 11381: 11378: 11377: 11360: 11356: 11335: 11331: 11322: 11318: 11316: 11313: 11312: 11286: 11282: 11273: 11269: 11267: 11264: 11263: 11246: 11242: 11240: 11237: 11236: 11219: 11215: 11213: 11210: 11209: 11188: 11184: 11175: 11171: 11169: 11166: 11165: 11144: 11140: 11131: 11127: 11125: 11122: 11121: 11101: 11097: 11088: 11084: 11079: 11076: 11075: 11059: 11056: 11055: 11034: 11030: 11009: 11005: 11003: 11000: 10999: 10980: 10976: 10955: 10951: 10949: 10946: 10945: 10922: 10918: 10909: 10905: 10900: 10897: 10896: 10876: 10872: 10858: 10855: 10854: 10838: 10835: 10834: 10817: 10813: 10793: 10790: 10789: 10770: 10767: 10766: 10750: 10747: 10746: 10745:, an algorithm 10729: 10725: 10705: 10702: 10701: 10695: 10693:Promise problem 10689: 10675:if and only if 10667:. Importantly, 10586:. Importantly, 10574:polynomial time 10556: 10534: 10530: 10522: 10519: 10518: 10493: 10490: 10489: 10469: 10466: 10465: 10449: 10446: 10445: 10411: 10408: 10407: 10391: 10388: 10387: 10371: 10368: 10367: 10351: 10348: 10347: 10327: 10323: 10314: 10310: 10302: 10299: 10298: 10279: 10276: 10275: 10256: 10253: 10252: 10236: 10233: 10232: 10204: 10201: 10200: 10190: 10184: 10162: 10159: 10158: 10133: 10130: 10129: 10112: 10111: 10105: 10104: 10067: 10059: 10052: 10048: 10024: 10023: 10017: 10016: 9999: 9996: 9995: 9978: 9974: 9954: 9951: 9950: 9934: 9931: 9930: 9914: 9906: 9898: 9895: 9894: 9878: 9869: 9865: 9845: 9842: 9841: 9778: 9775: 9774: 9758: 9755: 9754: 9729: 9726: 9725: 9708: 9704: 9684: 9681: 9680: 9664: 9661: 9660: 9644: 9635: 9631: 9611: 9608: 9607: 9578: 9572: 9532: 9529: 9528: 9503: 9500: 9499: 9478: 9474: 9454: 9451: 9450: 9433: 9432: 9427: 9424: 9423: 9398: 9395: 9394: 9377: 9373: 9353: 9350: 9349: 9333: 9324: 9320: 9300: 9297: 9296: 9269: 9266: 9265: 9244: 9243: 9238: 9235: 9234: 9214: 9211: 9210: 9189: 9188: 9186: 9183: 9182: 9163: 9157: 9133: 9099: 9093: 9090: 9083:needs expansion 9068: 9013:advice function 9009:Turing machines 8978: 8977: 8972: 8966: 8963: 8962: 8920: 8919: 8910: 8909: 8907: 8904: 8903: 8898:that is not in 8854: 8853: 8844: 8843: 8841: 8838: 8837: 8819: 8818: 8807: 8806: 8804: 8801: 8800: 8770: 8766: 8758: 8755: 8754: 8738: 8730: 8722: 8719: 8718: 8702: 8699: 8698: 8651: 8650: 8648: 8645: 8644: 8634: 8609: 8606: 8605: 8588: 8584: 8582: 8579: 8578: 8553: 8550: 8549: 8533: 8525: 8517: 8514: 8513: 8481: 8477: 8468: 8464: 8455: 8451: 8446: 8443: 8442: 8439:time complexity 8419: 8416: 8415: 8399: 8396: 8395: 8378: 8374: 8372: 8369: 8368: 8367:if the circuit 8336: 8332: 8323: 8319: 8310: 8306: 8301: 8298: 8297: 8281: 8278: 8277: 8261: 8258: 8257: 8241: 8238: 8237: 8221: 8218: 8217: 8185: 8181: 8179: 8176: 8175: 8174:if and only if 8159: 8156: 8155: 8139: 8136: 8135: 8119: 8116: 8115: 8099: 8096: 8095: 8079: 8076: 8075: 8058: 8054: 8052: 8049: 8048: 8016: 8012: 8003: 7999: 7990: 7986: 7981: 7978: 7977: 7945: 7941: 7939: 7936: 7935: 7915: 7912: 7911: 7891: 7887: 7866: 7862: 7853: 7849: 7840: 7836: 7828: 7825: 7824: 7808: 7805: 7804: 7787: 7783: 7762: 7758: 7749: 7745: 7743: 7740: 7739: 7704: 7700: 7679: 7675: 7673: 7670: 7669: 7650: 7647: 7646: 7630: 7627: 7626: 7613:(generally the 7586: 7583: 7582: 7570:used in modern 7563:Boolean circuit 7533: 7530: 7529: 7509: 7506: 7505: 7485: 7482: 7481: 7458: 7454: 7452: 7449: 7448: 7425: 7421: 7419: 7416: 7415: 7392: 7388: 7386: 7383: 7382: 7362: 7358: 7343: 7339: 7330: 7326: 7308: 7304: 7295: 7291: 7273: 7269: 7260: 7256: 7247: 7243: 7234: 7230: 7228: 7225: 7224: 7217: 7211: 7162: 7161: 7140: 7139: 7137: 7134: 7133: 7103: 7100: 7099: 7009: 6995: 6987: 6976: 6973: 6972: 6956: 6953: 6952: 6936: 6933: 6932: 6907: 6893: 6885: 6874: 6871: 6870: 6854: 6851: 6850: 6834: 6831: 6830: 6807: 6806: 6798: 6795: 6794: 6778: 6775: 6774: 6746: 6743: 6742: 6717: 6714: 6713: 6664: 6642: 6639: 6638: 6622: 6619: 6618: 6617:and a verifier 6602: 6599: 6598: 6556: 6550: 6463: 6462: 6453: 6452: 6443: 6442: 6440: 6437: 6436: 6370:have efficient 6354:two-sided error 6347:one-sided error 6316: 6313: 6312: 6296: 6293: 6292: 6276: 6273: 6272: 6201: 6162: 6151: 6149: 6146: 6145: 6129: 6126: 6125: 6109: 6106: 6105: 6069: 6058: 6056: 6053: 6052: 6036: 6033: 6032: 6016: 6013: 6012: 5992: 5989: 5988: 5972: 5969: 5968: 5952: 5949: 5948: 5932: 5929: 5928: 5907: 5901: 5792:Turing machines 5788: 5746: 5745: 5700: 5699: 5678: 5677: 5668: 5667: 5649: 5648: 5627: 5626: 5624: 5621: 5620: 5592: 5591: 5564: 5560: 5539: 5538: 5520: 5519: 5510: 5509: 5491: 5490: 5472: 5471: 5469: 5466: 5465: 5438: 5434: 5425: 5421: 5419: 5416: 5415: 5393: 5389: 5388: 5384: 5364: 5360: 5359: 5355: 5347: 5344: 5343: 5326: 5322: 5313: 5309: 5307: 5304: 5303: 5281: 5277: 5276: 5272: 5251: 5250: 5248: 5245: 5244: 5222: 5218: 5217: 5213: 5192: 5191: 5189: 5186: 5185: 5178: 5170:Main articles: 5168: 5115: 5104: 5103: 5099: 5095: 5074: 5073: 5054: 5050: 5046: 5025: 5024: 5022: 5019: 5018: 4984: 4981: 4980: 4963: 4959: 4948: 4945: 4944: 4919: 4916: 4915: 4912: 4906: 4901: 4842: 4839: 4838: 4818: 4815: 4814: 4788: 4785: 4784: 4779:and is also in 4760: 4757: 4756: 4753: 4718: 4715: 4714: 4698: 4695: 4694: 4693:is harder than 4674: 4671: 4670: 4646: 4643: 4642: 4635: 4615:Karp reductions 4611:Cook reductions 4576: 4573: 4572: 4548: 4545: 4544: 4527: 4523: 4515: 4512: 4511: 4495: 4492: 4491: 4488:polynomial-time 4471: 4468: 4467: 4451: 4448: 4447: 4431: 4428: 4427: 4411: 4408: 4407: 4391: 4388: 4387: 4352: 4349: 4348: 4324: 4321: 4320: 4303: 4299: 4291: 4288: 4287: 4271: 4268: 4267: 4251: 4248: 4247: 4231: 4228: 4227: 4211: 4208: 4207: 4191: 4188: 4187: 4165: 4162: 4161: 4154: 4148: 4139: 4138:runtimes where 4119: 4115: 4107: 4104: 4103: 4071: 4067: 4049: 4045: 4037: 4034: 4033: 4013: 4009: 3991: 3987: 3969: 3965: 3957: 3954: 3953: 3933: 3929: 3921: 3918: 3917: 3893: 3889: 3881: 3878: 3877: 3852: 3849: 3848: 3811: 3810: 3797: 3792: 3777: 3776: 3774: 3771: 3770: 3728: 3723: 3666: 3662: 3661: 3657: 3633: 3632: 3625: 3618: 3581: 3580: 3578: 3575: 3574: 3551: 3547: 3546: 3542: 3518: 3517: 3510: 3503: 3469: 3468: 3466: 3463: 3462: 3428: 3422: 3377: 3376: 3367: 3366: 3364: 3361: 3360: 3317: 3313: 3289: 3288: 3281: 3274: 3243: 3242: 3240: 3237: 3236: 3215: 3211: 3187: 3186: 3179: 3172: 3144: 3143: 3141: 3138: 3137: 3103: 3097: 3075: 3074: 3062: 3061: 3052: 3051: 3049: 3046: 3045: 2995: 2994: 2982: 2981: 2979: 2976: 2975: 2927: 2926: 2917: 2916: 2914: 2911: 2910: 2852: 2849: 2848: 2841: 2839:NL (complexity) 2833:Main articles: 2831: 2826: 2820: 2780: 2777: 2776: 2733: 2729: 2728: 2724: 2703: 2702: 2695: 2688: 2654: 2653: 2651: 2648: 2647: 2624: 2620: 2619: 2615: 2594: 2593: 2586: 2579: 2548: 2547: 2545: 2542: 2541: 2520: 2512:Main articles: 2510: 2485: 2484: 2475: 2474: 2472: 2469: 2468: 2444: 2443: 2434: 2433: 2431: 2428: 2427: 2362: 2361: 2352: 2351: 2349: 2346: 2345: 2324: 2276: 2273: 2272: 2251: 2243: 2236: 2232: 2212: 2209: 2208: 2189: 2186: 2185: 2169: 2166: 2165: 2148: 2144: 2124: 2121: 2120: 2104: 2101: 2100: 2084: 2081: 2080: 2064: 2061: 2060: 2037: 2034: 2033: 2032:that the input 2013: 2010: 2009: 1993: 1990: 1989: 1973: 1970: 1969: 1953: 1950: 1949: 1933: 1930: 1929: 1906: 1903: 1902: 1876:time complexity 1849: 1845: 1824: 1823: 1816: 1809: 1793: 1792: 1790: 1787: 1786: 1765: 1761: 1740: 1739: 1732: 1725: 1712: 1711: 1709: 1706: 1705: 1691:polynomial time 1680: 1678:NP (complexity) 1672:Main articles: 1670: 1665: 1663:Time complexity 1659: 1619: 1616: 1615: 1565: 1564: 1562: 1559: 1558: 1521: 1518: 1517: 1467: 1466: 1464: 1461: 1460: 1423: 1420: 1419: 1372: 1371: 1369: 1366: 1365: 1328: 1325: 1324: 1277: 1276: 1274: 1271: 1270: 1243: 1238: 1232: 1211: 1208: 1207: 1191: 1188: 1187: 1161: 1157: 1155: 1152: 1151: 1135: 1127: 1118: 1114: 1112: 1109: 1108: 1092: 1089: 1088: 1080: 1074: 1037: 1034: 1033: 1017: 1014: 1013: 987: 983: 981: 978: 977: 961: 953: 944: 940: 938: 935: 934: 918: 915: 914: 910:time complexity 906: 904:Time complexity 900: 847: 846: 837: 836: 834: 831: 830: 795: 793:Resource bounds 775:time complexity 759: 753: 741:time complexity 734:recognizability 700: 699: 697: 694: 693: 658: 652: 601: 534: 533: 531: 528: 527: 504: 501: 500: 466: 440: 439: 437: 434: 433: 410: 409: 407: 404: 403: 390:that represent 364: 356: 351: 333: 332: 330: 327: 326: 309: 308: 306: 303: 302: 279: 276: 275: 263:Intuitively, a 261: 253:polynomial time 211: 127:following way: 97:polynomial time 28: 23: 22: 15: 12: 11: 5: 14023: 14013: 14012: 14007: 14002: 13997: 13980: 13979: 13974: 13971: 13970: 13968: 13967: 13962: 13957: 13952: 13947: 13942: 13936: 13934: 13930: 13929: 13927: 13926: 13921: 13916: 13911: 13906: 13900: 13898: 13894: 13893: 13891: 13890: 13885: 13880: 13875: 13870: 13865: 13860: 13855: 13850: 13844: 13842: 13838: 13837: 13835: 13834: 13833: 13832: 13822: 13817: 13816: 13815: 13805: 13800: 13795: 13790: 13785: 13780: 13775: 13770: 13769: 13768: 13766:co-NP-complete 13763: 13758: 13753: 13743: 13737: 13735: 13731: 13730: 13728: 13727: 13722: 13717: 13712: 13707: 13702: 13697: 13696: 13695: 13685: 13680: 13675: 13670: 13669: 13668: 13658: 13653: 13648: 13643: 13638: 13633: 13628: 13623: 13617: 13615: 13611: 13610: 13603: 13602: 13595: 13588: 13580: 13574: 13573: 13559: 13556:on 2016-04-16. 13542: 13527: 13524: 13523: 13522: 13494: 13481: 13460: 13448:978-0132288064 13447: 13422: 13387: 13370: 13357: 13321: 13296: 13283: 13263: 13236: 13219: 13213: 13185:Arora, Sanjeev 13181: 13159: 13156: 13153: 13152: 13148:Goldreich 2006 13140: 13136:Goldreich 2006 13128: 13124:Goldreich 2006 13116: 13101: 13089: 13087:, p. 344. 13070: 13053: 13041: 13039:, p. 342. 13029: 13017: 13005: 13003:, p. 286. 12993: 12991:, p. 355. 12981: 12979:, p. 144. 12969: 12957: 12945: 12933: 12918: 12916:, p. 321. 12903: 12901:, p. 320. 12891: 12879: 12867: 12855: 12843: 12841:, p. 255. 12831: 12819: 12807: 12803:Johnson (1990) 12794: 12793: 12791: 12788: 12785: 12784: 12771: 12768: 12765: 12762: 12759: 12756: 12736: 12733: 12730: 12727: 12724: 12721: 12701: 12681: 12678: 12675: 12655: 12652: 12649: 12646: 12629: 12628: 12626: 12623: 12622: 12621: 12614: 12611: 12608: 12607: 12604: 12603: 12593: 12592: 12584: 12583: 12580: 12579: 12569: 12568: 12561: 12553: 12552: 12549: 12548: 12539: 12531: 12530: 12523: 12516: 12508: 12507: 12504: 12503: 12494: 12487: 12479: 12478: 12471: 12469: 12462: 12455: 12448: 12440: 12439: 12432: 12430: 12427: 12426: 12417: 12410: 12403: 12395: 12394: 12387: 12385: 12378: 12371: 12364: 12356: 12355: 12352: 12351: 12342: 12340: 12337: 12336: 12327: 12324: 12323: 12314: 12307: 12299: 12298: 12291: 12289: 12282: 12275: 12268: 12260: 12259: 12252: 12250: 12243: 12236: 12229: 12226: 12225: 12215: 12214: 12207: 12205: 12198: 12191: 12184: 12176: 12175: 12172: 12171: 12161: 12160: 12152: 12151: 12148: 12147: 12137: 12136: 12128: 12127: 12124: 12123: 12113: 12112: 12104: 12103: 12100: 12099: 12089: 12088: 12080: 12079: 12076: 12075: 12065: 12064: 12056: 12055: 12052: 12051: 12042: 12040: 12037: 12036: 12026: 12025: 12018: 12016: 12009: 12006: 12005: 12002: 12001: 11992: 11955: 11952: 11921: 11916: 11910: 11906: 11902: 11899: 11896: 11893: 11884:is implicitly 11867: 11840: 11836: 11833: 11813: 11802: 11801: 11800: 11799: 11788: 11785: 11782: 11779: 11776: 11773: 11770: 11761: 11757: 11754: 11743: 11732: 11729: 11726: 11723: 11720: 11717: 11714: 11705: 11701: 11698: 11675: 11651: 11642: 11638: 11629: 11625: 11602: 11599: 11584: 11580: 11576: 11573: 11570: 11567: 11564: 11561: 11526: 11523: 11514: 11493: 11467: 11462: 11456: 11452: 11448: 11445: 11442: 11439: 11413: 11386: 11363: 11359: 11355: 11352: 11349: 11346: 11343: 11334: 11330: 11321: 11297: 11294: 11285: 11281: 11272: 11245: 11218: 11187: 11183: 11174: 11143: 11139: 11130: 11109: 11100: 11096: 11087: 11083: 11063: 11052: 11051: 11037: 11033: 11029: 11026: 11023: 11020: 11017: 11008: 10997: 10983: 10979: 10975: 10972: 10969: 10966: 10963: 10954: 10930: 10921: 10917: 10908: 10904: 10879: 10875: 10871: 10868: 10865: 10862: 10842: 10820: 10816: 10812: 10809: 10806: 10803: 10800: 10797: 10774: 10754: 10732: 10728: 10724: 10721: 10718: 10715: 10712: 10709: 10691:Main article: 10688: 10685: 10555: 10552: 10537: 10533: 10529: 10526: 10506: 10503: 10500: 10497: 10473: 10453: 10433: 10430: 10427: 10424: 10421: 10418: 10415: 10395: 10375: 10355: 10344: 10343: 10330: 10326: 10322: 10317: 10313: 10309: 10306: 10283: 10260: 10240: 10220: 10217: 10214: 10211: 10208: 10186:Main article: 10183: 10180: 10179: 10178: 10166: 10146: 10143: 10140: 10137: 10115: 10108: 10103: 10100: 10097: 10094: 10091: 10088: 10085: 10082: 10079: 10074: 10070: 10066: 10062: 10058: 10055: 10051: 10047: 10044: 10041: 10038: 10035: 10032: 10027: 10020: 10015: 10012: 10009: 10006: 10003: 9981: 9977: 9973: 9970: 9967: 9964: 9961: 9958: 9938: 9917: 9913: 9909: 9905: 9902: 9881: 9877: 9872: 9868: 9864: 9861: 9858: 9855: 9852: 9849: 9805:), so too can 9795: 9794: 9782: 9762: 9742: 9739: 9736: 9733: 9711: 9707: 9703: 9700: 9697: 9694: 9691: 9688: 9668: 9647: 9643: 9638: 9634: 9630: 9627: 9624: 9621: 9618: 9615: 9574:Main article: 9571: 9568: 9560:network design 9536: 9516: 9513: 9510: 9507: 9481: 9477: 9473: 9470: 9467: 9464: 9461: 9458: 9431: 9411: 9408: 9405: 9402: 9380: 9376: 9372: 9369: 9366: 9363: 9360: 9357: 9336: 9332: 9327: 9323: 9319: 9316: 9313: 9310: 9307: 9304: 9273: 9264:simple cycles 9242: 9218: 9169:asks not only 9159:Main article: 9156: 9153: 9132: 9129: 9101: 9100: 9080: 9078: 9067: 9064: 8981: 8975: 8971: 8926: 8923: 8918: 8913: 8852: 8817: 8811: 8787: 8784: 8781: 8778: 8773: 8769: 8765: 8762: 8741: 8737: 8733: 8729: 8726: 8717:is a function 8706: 8686: 8683: 8680: 8677: 8674: 8671: 8666: 8663: 8660: 8657: 8654: 8633: 8630: 8613: 8591: 8587: 8566: 8563: 8560: 8557: 8536: 8532: 8528: 8524: 8521: 8501: 8498: 8495: 8492: 8489: 8484: 8480: 8476: 8471: 8467: 8463: 8458: 8454: 8450: 8434:is its input. 8423: 8403: 8381: 8377: 8356: 8353: 8350: 8347: 8344: 8339: 8335: 8331: 8326: 8322: 8318: 8313: 8309: 8305: 8285: 8265: 8245: 8225: 8205: 8202: 8199: 8196: 8193: 8188: 8184: 8163: 8143: 8123: 8103: 8083: 8061: 8057: 8036: 8033: 8030: 8027: 8024: 8019: 8015: 8011: 8006: 8002: 7998: 7993: 7989: 7985: 7974:circuit family 7948: 7944: 7919: 7910:. The circuit 7899: 7894: 7890: 7886: 7883: 7880: 7877: 7874: 7869: 7865: 7861: 7856: 7852: 7848: 7843: 7839: 7835: 7832: 7812: 7790: 7786: 7782: 7779: 7776: 7773: 7770: 7765: 7761: 7757: 7752: 7748: 7727: 7724: 7721: 7718: 7715: 7712: 7707: 7703: 7699: 7696: 7693: 7690: 7687: 7682: 7678: 7654: 7634: 7590: 7558:Turing machine 7537: 7513: 7489: 7469: 7466: 7461: 7457: 7436: 7433: 7428: 7424: 7403: 7400: 7395: 7391: 7370: 7365: 7361: 7357: 7354: 7351: 7346: 7342: 7338: 7333: 7329: 7325: 7322: 7319: 7316: 7311: 7307: 7303: 7298: 7294: 7290: 7287: 7284: 7281: 7276: 7272: 7268: 7263: 7259: 7255: 7250: 7246: 7242: 7237: 7233: 7213:Main article: 7210: 7207: 7179: 7176: 7173: 7168: 7165: 7160: 7157: 7154: 7151: 7146: 7143: 7113: 7110: 7107: 7032: 7031: 7017: 7014: 7008: 7005: 7002: 6994: 6986: 6983: 6980: 6960: 6940: 6929: 6915: 6912: 6906: 6903: 6900: 6892: 6884: 6881: 6878: 6858: 6838: 6813: 6810: 6805: 6802: 6782: 6762: 6759: 6756: 6753: 6750: 6721: 6674:Turing machine 6663: 6660: 6646: 6626: 6606: 6552:Main article: 6549: 6546: 6461: 6451: 6320: 6300: 6280: 6200: 6197: 6196: 6195: 6184: 6181: 6178: 6175: 6172: 6169: 6161: 6158: 6133: 6113: 6102: 6091: 6088: 6085: 6082: 6079: 6076: 6068: 6065: 6040: 6020: 5996: 5976: 5956: 5936: 5917:Turing machine 5903:Main article: 5900: 5897: 5893: 5892: 5874: 5850: 5826: 5787: 5784: 5764: 5763: 5749: 5744: 5741: 5738: 5735: 5732: 5729: 5726: 5723: 5720: 5717: 5714: 5711: 5708: 5703: 5696: 5693: 5690: 5687: 5684: 5681: 5676: 5671: 5666: 5663: 5660: 5657: 5652: 5645: 5642: 5639: 5636: 5633: 5630: 5610: 5609: 5595: 5590: 5587: 5584: 5581: 5578: 5575: 5572: 5567: 5563: 5559: 5556: 5553: 5550: 5547: 5542: 5535: 5532: 5529: 5526: 5523: 5518: 5513: 5508: 5505: 5502: 5499: 5494: 5487: 5484: 5481: 5478: 5475: 5441: 5437: 5433: 5428: 5424: 5403: 5396: 5392: 5387: 5383: 5380: 5377: 5374: 5367: 5363: 5358: 5354: 5351: 5329: 5325: 5321: 5316: 5312: 5291: 5284: 5280: 5275: 5271: 5266: 5263: 5260: 5257: 5254: 5232: 5225: 5221: 5216: 5212: 5207: 5204: 5201: 5198: 5195: 5167: 5164: 5140: 5139: 5128: 5124: 5118: 5113: 5110: 5107: 5102: 5098: 5092: 5089: 5086: 5083: 5080: 5077: 5072: 5068: 5063: 5060: 5057: 5053: 5049: 5043: 5040: 5037: 5034: 5031: 5028: 5003: 5000: 4997: 4994: 4991: 4988: 4966: 4962: 4958: 4955: 4952: 4932: 4929: 4926: 4923: 4908:Main article: 4905: 4902: 4900: 4897: 4846: 4822: 4803:is said to be 4792: 4764: 4752: 4749: 4722: 4702: 4678: 4650: 4634: 4631: 4595: 4592: 4589: 4586: 4583: 4580: 4570:if and only if 4558: 4555: 4552: 4530: 4526: 4522: 4519: 4499: 4475: 4455: 4435: 4415: 4395: 4371: 4368: 4365: 4362: 4359: 4356: 4346:if and only if 4334: 4331: 4328: 4306: 4302: 4298: 4295: 4275: 4255: 4235: 4215: 4195: 4175: 4172: 4169: 4147: 4144: 4127: 4122: 4118: 4114: 4111: 4079: 4074: 4070: 4066: 4063: 4060: 4057: 4052: 4048: 4044: 4041: 4021: 4016: 4012: 4008: 4005: 4002: 3999: 3994: 3990: 3986: 3983: 3980: 3977: 3972: 3968: 3964: 3961: 3941: 3936: 3932: 3928: 3925: 3901: 3896: 3892: 3888: 3885: 3865: 3862: 3859: 3856: 3819: 3814: 3809: 3804: 3801: 3795: 3791: 3788: 3785: 3727: 3724: 3722: 3719: 3688: 3687: 3676: 3669: 3665: 3660: 3656: 3651: 3648: 3645: 3642: 3639: 3636: 3628: 3624: 3621: 3617: 3613: 3608: 3605: 3602: 3599: 3596: 3593: 3590: 3587: 3584: 3572: 3561: 3554: 3550: 3545: 3541: 3536: 3533: 3530: 3527: 3524: 3521: 3513: 3509: 3506: 3502: 3498: 3493: 3490: 3487: 3484: 3481: 3478: 3475: 3472: 3424:Main article: 3421: 3418: 3395: 3392: 3389: 3386: 3383: 3380: 3375: 3370: 3337: 3336: 3325: 3320: 3316: 3312: 3307: 3304: 3301: 3298: 3295: 3292: 3284: 3280: 3277: 3273: 3269: 3264: 3261: 3258: 3255: 3252: 3249: 3246: 3234: 3223: 3218: 3214: 3210: 3205: 3202: 3199: 3196: 3193: 3190: 3182: 3178: 3175: 3171: 3167: 3162: 3159: 3156: 3153: 3150: 3147: 3099:Main article: 3096: 3093: 3078: 3073: 3068: 3065: 3060: 3055: 3042: 3041: 3030: 3027: 3024: 3021: 3018: 3013: 3010: 3007: 3004: 3001: 2998: 2993: 2988: 2985: 2973: 2962: 2959: 2956: 2953: 2950: 2945: 2942: 2939: 2936: 2933: 2930: 2925: 2920: 2868: 2865: 2862: 2859: 2856: 2835:L (complexity) 2830: 2827: 2822:Main article: 2819: 2816: 2784: 2755: 2754: 2743: 2736: 2732: 2727: 2723: 2718: 2715: 2712: 2709: 2706: 2698: 2694: 2691: 2687: 2683: 2678: 2675: 2672: 2669: 2666: 2663: 2660: 2657: 2645: 2634: 2627: 2623: 2618: 2614: 2609: 2606: 2603: 2600: 2597: 2589: 2585: 2582: 2578: 2574: 2569: 2566: 2563: 2560: 2557: 2554: 2551: 2509: 2506: 2491: 2488: 2483: 2478: 2450: 2447: 2442: 2437: 2368: 2365: 2360: 2355: 2323: 2320: 2312:nondeterminism 2308: 2307: 2295: 2292: 2289: 2286: 2283: 2280: 2258: 2254: 2250: 2246: 2242: 2239: 2235: 2231: 2228: 2225: 2222: 2219: 2216: 2205:if and only if 2193: 2173: 2151: 2147: 2143: 2140: 2137: 2134: 2131: 2128: 2108: 2088: 2068: 2041: 2017: 1997: 1977: 1957: 1948:, and accepts 1937: 1910: 1869: 1868: 1857: 1852: 1848: 1844: 1839: 1836: 1833: 1830: 1827: 1819: 1815: 1812: 1808: 1804: 1799: 1796: 1784: 1773: 1768: 1764: 1760: 1755: 1752: 1749: 1746: 1743: 1735: 1731: 1728: 1724: 1720: 1715: 1674:P (complexity) 1669: 1666: 1661:Main article: 1658: 1655: 1654: 1653: 1641: 1638: 1635: 1632: 1629: 1626: 1623: 1603: 1600: 1597: 1594: 1591: 1588: 1583: 1580: 1577: 1574: 1571: 1568: 1555: 1543: 1540: 1537: 1534: 1531: 1528: 1525: 1505: 1502: 1499: 1496: 1493: 1490: 1485: 1482: 1479: 1476: 1473: 1470: 1457: 1445: 1442: 1439: 1436: 1433: 1430: 1427: 1407: 1404: 1401: 1398: 1395: 1392: 1387: 1384: 1381: 1378: 1375: 1362: 1350: 1347: 1344: 1341: 1338: 1335: 1332: 1312: 1309: 1306: 1303: 1300: 1297: 1292: 1289: 1286: 1283: 1280: 1263:big O notation 1242: 1239: 1231: 1228: 1215: 1195: 1175: 1172: 1169: 1164: 1160: 1138: 1134: 1130: 1126: 1121: 1117: 1096: 1076:Main article: 1073: 1070: 1041: 1021: 1001: 998: 995: 990: 986: 964: 960: 956: 952: 947: 943: 922: 902:Main article: 899: 896: 891:most efficient 868: 865: 862: 859: 856: 853: 850: 845: 840: 803:rate of growth 794: 791: 755:Main article: 752: 749: 670:Turing machine 656:Turing machine 654:Main article: 651: 648: 625:Turing machine 600: 597: 596: 595: 589: 584: 572: 508: 498:natural number 465: 462: 392:binary numbers 371: 366: is prime 363: 359: 354: 350: 347: 344: 341: 283: 273:natural number 260: 257: 227:Turing machine 210: 207: 203:nondeterminism 87:Turing machine 26: 9: 6: 4: 3: 2: 14022: 14011: 14008: 14006: 14003: 14001: 13998: 13996: 13993: 13992: 13990: 13977: 13972: 13966: 13963: 13961: 13958: 13956: 13953: 13951: 13948: 13946: 13943: 13941: 13938: 13937: 13935: 13931: 13925: 13922: 13920: 13917: 13915: 13912: 13910: 13907: 13905: 13902: 13901: 13899: 13895: 13889: 13886: 13884: 13881: 13879: 13876: 13874: 13871: 13869: 13866: 13864: 13861: 13859: 13856: 13854: 13851: 13849: 13846: 13845: 13843: 13839: 13831: 13828: 13827: 13826: 13823: 13821: 13818: 13814: 13811: 13810: 13809: 13806: 13804: 13801: 13799: 13796: 13794: 13791: 13789: 13786: 13784: 13781: 13779: 13776: 13774: 13771: 13767: 13764: 13762: 13759: 13757: 13754: 13752: 13749: 13748: 13747: 13744: 13742: 13739: 13738: 13736: 13732: 13726: 13723: 13721: 13718: 13716: 13713: 13711: 13708: 13706: 13703: 13701: 13698: 13694: 13691: 13690: 13689: 13686: 13684: 13681: 13679: 13676: 13674: 13671: 13667: 13664: 13663: 13662: 13659: 13657: 13654: 13652: 13649: 13647: 13644: 13642: 13639: 13637: 13634: 13632: 13629: 13627: 13624: 13622: 13619: 13618: 13616: 13612: 13608: 13601: 13596: 13594: 13589: 13587: 13582: 13581: 13578: 13571: 13567: 13563: 13562:Michael Garey 13560: 13555: 13551: 13547: 13546:Neil Immerman 13543: 13540: 13536: 13533: 13530: 13529: 13516: 13512: 13511: 13503: 13499: 13498:Watrous, John 13495: 13488: 13484: 13482:0-534-95097-3 13478: 13471: 13470: 13465: 13461: 13454: 13450: 13444: 13440: 13439:Prentice Hall 13433: 13432: 13427: 13423: 13408: 13404: 13400: 13393: 13388: 13384: 13380: 13376: 13371: 13364: 13360: 13354: 13350: 13346: 13339: 13338: 13330: 13326: 13322: 13315: 13311: 13310: 13302: 13297: 13290: 13286: 13284:9780387949734 13280: 13276: 13269: 13264: 13260: 13256: 13252: 13245: 13241: 13237: 13233: 13229: 13225: 13220: 13216: 13210: 13206: 13202: 13197: 13196: 13190: 13186: 13182: 13178: 13174: 13170: 13166: 13162: 13161: 13149: 13144: 13137: 13132: 13125: 13120: 13113: 13108: 13106: 13098: 13093: 13086: 13081: 13079: 13077: 13075: 13067: 13062: 13060: 13058: 13050: 13045: 13038: 13033: 13026: 13021: 13014: 13009: 13002: 12997: 12990: 12985: 12978: 12973: 12966: 12961: 12954: 12953:Aaronson 2017 12949: 12942: 12941:Aaronson 2017 12937: 12930: 12929:Aaronson 2017 12925: 12923: 12915: 12910: 12908: 12900: 12895: 12888: 12887:Aaronson 2017 12883: 12876: 12871: 12864: 12863:Aaronson 2017 12859: 12853:, p. 12. 12852: 12851:Aaronson 2017 12847: 12840: 12835: 12828: 12823: 12817:, p. 28. 12816: 12811: 12804: 12799: 12795: 12769: 12766: 12763: 12760: 12757: 12754: 12734: 12731: 12728: 12725: 12722: 12719: 12699: 12679: 12676: 12673: 12653: 12650: 12647: 12644: 12634: 12630: 12620: 12617: 12616: 12602: 12599: 12598: 12594: 12590: 12585: 12578: 12575: 12574: 12570: 12566: 12559: 12555: 12554: 12547: 12544: 12543: 12537: 12533: 12532: 12528: 12524: 12521: 12517: 12514: 12510: 12509: 12502: 12499: 12498: 12492: 12488: 12485: 12481: 12480: 12476: 12472: 12470: 12467: 12463: 12460: 12456: 12453: 12449: 12446: 12442: 12441: 12437: 12433: 12425: 12422: 12421: 12418: 12415: 12411: 12408: 12404: 12401: 12397: 12396: 12392: 12388: 12386: 12383: 12379: 12376: 12372: 12369: 12365: 12362: 12358: 12357: 12350: 12347: 12346: 12341: 12335: 12332: 12331: 12328: 12322: 12319: 12318: 12315: 12312: 12308: 12305: 12301: 12300: 12296: 12292: 12290: 12287: 12283: 12280: 12276: 12273: 12269: 12266: 12262: 12261: 12257: 12253: 12251: 12248: 12244: 12241: 12237: 12234: 12230: 12224: 12221: 12220: 12217: 12216: 12212: 12208: 12206: 12203: 12199: 12196: 12192: 12189: 12182: 12178: 12177: 12170: 12167: 12166: 12162: 12158: 12153: 12146: 12143: 12142: 12138: 12134: 12129: 12122: 12119: 12118: 12114: 12110: 12105: 12098: 12095: 12094: 12090: 12086: 12081: 12074: 12071: 12070: 12066: 12062: 12057: 12050: 12047: 12046: 12041: 12035: 12032: 12031: 12027: 12023: 12019: 12014: 12010: 12007: 12000: 11997: 11996: 11990: 11987: 11985: 11981: 11977: 11973: 11969: 11965: 11961: 11951: 11949: 11944: 11939: 11914: 11908: 11900: 11897: 11894: 11834: 11831: 11811: 11786: 11783: 11777: 11771: 11768: 11755: 11752: 11744: 11730: 11727: 11721: 11715: 11712: 11699: 11696: 11688: 11687: 11673: 11665: 11636: 11615: 11612: 11611: 11610: 11608: 11598: 11582: 11574: 11571: 11568: 11562: 11559: 11551: 11547: 11542: 11540: 11524: 11521: 11491: 11460: 11454: 11446: 11443: 11440: 11361: 11353: 11350: 11347: 11341: 11328: 11309: 11292: 11279: 11207: 11181: 11164:. Strings in 11163: 11137: 11094: 11061: 11035: 11027: 11024: 11021: 11015: 10998: 10981: 10973: 10970: 10967: 10961: 10944: 10943: 10942: 10915: 10893: 10877: 10869: 10866: 10863: 10840: 10818: 10810: 10807: 10804: 10798: 10795: 10788: 10772: 10752: 10730: 10722: 10719: 10716: 10710: 10707: 10699: 10694: 10684: 10682: 10678: 10674: 10670: 10666: 10665: 10660: 10659: 10654: 10650: 10645: 10643: 10639: 10635: 10631: 10627: 10623: 10619: 10615: 10611: 10607: 10603: 10599: 10598: 10594: 10589: 10585: 10584: 10579: 10575: 10571: 10567: 10563: 10562: 10551: 10535: 10527: 10524: 10501: 10495: 10487: 10471: 10451: 10431: 10428: 10422: 10419: 10416: 10393: 10373: 10353: 10328: 10320: 10315: 10307: 10304: 10297: 10296: 10295: 10274: 10258: 10238: 10218: 10212: 10209: 10206: 10199: 10195: 10189: 10164: 10141: 10135: 10101: 10098: 10092: 10089: 10086: 10080: 10077: 10064: 10053: 10045: 10042: 10039: 10033: 10030: 10013: 10007: 10001: 9979: 9971: 9968: 9965: 9959: 9956: 9936: 9903: 9900: 9870: 9862: 9859: 9856: 9850: 9847: 9839: 9836: 9835: 9834: 9832: 9828: 9824: 9820: 9816: 9812: 9808: 9804: 9800: 9780: 9760: 9737: 9731: 9709: 9701: 9698: 9695: 9689: 9686: 9666: 9636: 9628: 9625: 9622: 9616: 9613: 9605: 9602: 9601: 9600: 9598: 9594: 9590: 9586: 9582: 9577: 9567: 9565: 9561: 9557: 9553: 9548: 9534: 9511: 9505: 9497: 9479: 9471: 9468: 9465: 9459: 9456: 9406: 9400: 9378: 9370: 9367: 9364: 9358: 9355: 9325: 9317: 9314: 9311: 9305: 9302: 9294: 9290: 9285: 9271: 9263: 9232: 9216: 9208: 9180: 9176: 9172: 9168: 9162: 9152: 9150: 9146: 9142: 9138: 9128: 9126: 9125: 9120: 9116: 9115: 9110: 9109: 9097: 9088: 9084: 9081:This section 9079: 9076: 9072: 9071: 9063: 9061: 9057: 9053: 9049: 9045: 9041: 9040:directed path 9037: 9033: 9032: 9027: 9026: 9021: 9016: 9014: 9010: 9006: 9002: 8998: 8973: 8961:collapses to 8960: 8956: 8952: 8951: 8946: 8942: 8916: 8901: 8897: 8893: 8892: 8888: 8883: 8879: 8877: 8873: 8850: 8835: 8815: 8779: 8771: 8767: 8760: 8727: 8724: 8704: 8678: 8672: 8641: 8640: 8629: 8627: 8611: 8589: 8585: 8561: 8555: 8522: 8519: 8496: 8493: 8490: 8487: 8482: 8478: 8474: 8469: 8465: 8461: 8456: 8452: 8440: 8435: 8421: 8401: 8379: 8375: 8351: 8348: 8345: 8342: 8337: 8333: 8329: 8324: 8320: 8316: 8311: 8307: 8283: 8263: 8243: 8223: 8203: 8200: 8194: 8186: 8182: 8161: 8141: 8121: 8101: 8081: 8059: 8055: 8031: 8028: 8025: 8022: 8017: 8013: 8009: 8004: 8000: 7996: 7991: 7987: 7975: 7971: 7967: 7962: 7946: 7942: 7933: 7917: 7892: 7888: 7884: 7881: 7878: 7875: 7872: 7867: 7863: 7859: 7854: 7850: 7841: 7837: 7833: 7830: 7810: 7788: 7784: 7780: 7777: 7774: 7771: 7768: 7763: 7759: 7755: 7750: 7746: 7722: 7719: 7716: 7705: 7697: 7694: 7691: 7685: 7680: 7676: 7668: 7652: 7632: 7624: 7620: 7616: 7612: 7608: 7604: 7588: 7579: 7577: 7573: 7569: 7565: 7564: 7559: 7551: 7527: 7511: 7503: 7487: 7467: 7464: 7459: 7455: 7434: 7431: 7426: 7422: 7401: 7398: 7393: 7389: 7363: 7359: 7352: 7344: 7340: 7336: 7331: 7327: 7317: 7309: 7305: 7301: 7296: 7292: 7282: 7274: 7270: 7266: 7261: 7257: 7253: 7248: 7244: 7235: 7231: 7221: 7216: 7206: 7204: 7203: 7198: 7197: 7191: 7174: 7158: 7152: 7131: 7127: 7111: 7108: 7105: 7097: 7093: 7089: 7085: 7081: 7076: 7072: 7068: 7064: 7060: 7059: 7054: 7049: 7047: 7043: 7042: 7037: 7015: 7012: 7006: 7000: 6992: 6984: 6958: 6938: 6930: 6913: 6910: 6904: 6898: 6890: 6882: 6856: 6836: 6828: 6827: 6826: 6803: 6800: 6780: 6757: 6754: 6751: 6740: 6739: 6733: 6719: 6711: 6707: 6703: 6702:probabilistic 6698: 6693: 6691: 6687: 6683: 6679: 6675: 6671: 6670: 6659: 6644: 6624: 6604: 6596: 6587: 6583: 6581: 6577: 6573: 6569: 6568: 6563: 6562: 6555: 6545: 6543: 6542: 6537: 6536: 6531: 6530: 6524: 6522: 6518: 6514: 6510: 6506: 6502: 6498: 6494: 6490: 6486: 6482: 6459: 6449: 6434: 6430: 6426: 6422: 6418: 6414: 6410: 6406: 6402: 6398: 6394: 6392: 6391: 6385: 6383: 6382: 6377: 6373: 6369: 6365: 6361: 6360: 6355: 6350: 6348: 6344: 6340: 6336: 6335: 6318: 6298: 6278: 6270: 6266: 6265: 6259: 6257: 6253: 6252: 6246: 6244: 6243: 6238: 6237: 6232: 6231: 6226: 6225: 6220: 6219: 6210: 6205: 6182: 6179: 6176: 6173: 6167: 6159: 6144:implies that 6131: 6111: 6103: 6089: 6086: 6083: 6080: 6074: 6066: 6051:implies that 6038: 6018: 6010: 6009: 6008: 5994: 5974: 5954: 5934: 5924: 5922: 5918: 5914: 5913: 5906: 5896: 5891: 5890: 5885: 5884: 5879: 5875: 5873: 5872: 5867: 5866: 5861: 5860: 5855: 5851: 5849: 5848: 5843: 5842: 5837: 5836: 5831: 5827: 5825: 5824: 5819: 5818: 5813: 5812: 5807: 5806: 5801: 5797: 5796: 5795: 5793: 5783: 5781: 5777: 5773: 5769: 5736: 5730: 5724: 5721: 5718: 5712: 5706: 5674: 5661: 5655: 5619: 5618: 5617: 5615: 5582: 5576: 5570: 5565: 5561: 5557: 5551: 5545: 5516: 5503: 5497: 5464: 5463: 5462: 5460: 5455: 5439: 5435: 5431: 5426: 5422: 5394: 5390: 5385: 5378: 5375: 5365: 5361: 5356: 5349: 5327: 5323: 5319: 5314: 5310: 5282: 5278: 5273: 5223: 5219: 5214: 5183: 5177: 5173: 5163: 5159: 5157: 5153: 5149: 5145: 5126: 5122: 5116: 5111: 5108: 5105: 5100: 5096: 5070: 5066: 5061: 5058: 5055: 5051: 5047: 5017: 5016: 5015: 5001: 4998: 4992: 4986: 4964: 4956: 4950: 4927: 4921: 4911: 4896: 4894: 4891: =  4890: 4886: 4882: 4878: 4874: 4870: 4868: 4862: 4860: 4844: 4836: 4820: 4812: 4808: 4807: 4790: 4782: 4778: 4762: 4755:If a problem 4748: 4746: 4745: 4740: 4736: 4720: 4700: 4692: 4676: 4668: 4664: 4648: 4640: 4630: 4628: 4624: 4620: 4616: 4612: 4607: 4593: 4590: 4584: 4578: 4571: 4556: 4553: 4550: 4528: 4520: 4517: 4497: 4489: 4473: 4453: 4433: 4413: 4393: 4383: 4369: 4366: 4360: 4354: 4347: 4332: 4329: 4326: 4304: 4296: 4293: 4273: 4253: 4233: 4213: 4193: 4173: 4170: 4167: 4159: 4153: 4143: 4120: 4116: 4109: 4101: 4097: 4093: 4072: 4068: 4061: 4058: 4050: 4046: 4039: 4014: 4010: 4003: 4000: 3992: 3988: 3981: 3978: 3970: 3966: 3959: 3934: 3930: 3923: 3915: 3894: 3890: 3883: 3860: 3854: 3845: 3843: 3839: 3835: 3834: 3807: 3799: 3789: 3783: 3768: 3764: 3760: 3755: 3753: 3749: 3745: 3741: 3737: 3733: 3718: 3716: 3712: 3708: 3704: 3700: 3696: 3692: 3667: 3663: 3658: 3622: 3619: 3615: 3611: 3573: 3552: 3548: 3543: 3507: 3504: 3500: 3496: 3461: 3460: 3459: 3457: 3453: 3449: 3448: 3443: 3442: 3437: 3433: 3427: 3417: 3415: 3411: 3373: 3358: 3354: 3350: 3346: 3342: 3318: 3314: 3278: 3275: 3271: 3267: 3235: 3216: 3212: 3176: 3173: 3169: 3165: 3136: 3135: 3134: 3132: 3128: 3124: 3123: 3118: 3117: 3112: 3108: 3102: 3092: 3071: 3058: 3025: 3022: 3019: 2991: 2974: 2957: 2954: 2951: 2923: 2909: 2908: 2907: 2905: 2901: 2897: 2893: 2889: 2886: 2885:computability 2882: 2866: 2863: 2860: 2857: 2854: 2846: 2840: 2836: 2825: 2815: 2813: 2809: 2805: 2801: 2797: 2782: 2775: 2771: 2767: 2763: 2759: 2734: 2730: 2725: 2692: 2689: 2685: 2681: 2646: 2625: 2621: 2616: 2583: 2580: 2576: 2572: 2540: 2539: 2538: 2536: 2532: 2528: 2524: 2519: 2515: 2505: 2481: 2466: 2440: 2425: 2421: 2417: 2412: 2408: 2404: 2400: 2396: 2392: 2388: 2384: 2358: 2343: 2342: 2338: 2333: 2329: 2319: 2317: 2313: 2290: 2287: 2284: 2278: 2248: 2237: 2229: 2226: 2223: 2217: 2214: 2206: 2191: 2171: 2149: 2141: 2138: 2135: 2129: 2126: 2106: 2086: 2066: 2058: 2055: 2054: 2053: 2039: 2031: 2015: 1995: 1975: 1955: 1935: 1927: 1923: 1908: 1900: 1899:deterministic 1896: 1892: 1888: 1883: 1881: 1877: 1873: 1850: 1846: 1813: 1810: 1806: 1802: 1785: 1766: 1762: 1729: 1726: 1722: 1718: 1704: 1703: 1702: 1700: 1696: 1692: 1688: 1684: 1679: 1675: 1664: 1633: 1627: 1621: 1595: 1589: 1556: 1535: 1529: 1523: 1497: 1491: 1458: 1437: 1431: 1425: 1399: 1393: 1363: 1342: 1336: 1330: 1304: 1298: 1268: 1267: 1266: 1264: 1260: 1256: 1252: 1248: 1237: 1227: 1213: 1193: 1170: 1162: 1158: 1124: 1119: 1115: 1094: 1085: 1079: 1069: 1067: 1063: 1059: 1053: 1039: 1019: 996: 988: 984: 950: 945: 941: 920: 911: 905: 895: 892: 887: 882: 843: 828: 824: 820: 819: 814: 810: 809: 804: 800: 790: 786: 784: 780: 776: 771: 763: 758: 748: 746: 742: 737: 735: 731: 727: 723: 719: 690: 688: 687:deterministic 682: 680: 676: 671: 662: 657: 647: 645: 641: 636: 634: 630: 626: 621: 619: 614: 610: 606: 593: 590: 588: 585: 582: 581: 576: 573: 570: 569: 564: 561: 560: 559: 555: 553: 525: 521: 506: 499: 495: 491: 483: 479: 475: 470: 461: 459: 431: 430: 401: 397: 393: 389: 385: 361: 348: 345: 339: 300: 296: 281: 274: 270: 266: 256: 254: 250: 246: 242: 241: 236: 232: 229:with bounded 228: 224: 220: 216: 206: 204: 200: 196: 192: 191: 187: 182: 181:open problems 178: 174: 173: 168: 167: 162: 161: 156: 155: 150: 149: 144: 143: 138: 137: 132: 131: 124: 122: 118: 114: 110: 106: 102: 98: 94: 93: 88: 84: 80: 76: 72: 67: 65: 61: 57: 53: 49: 45: 41: 32: 19: 13606: 13569: 13554:the original 13508: 13487:the original 13468: 13430: 13426:Rich, Elaine 13414:. Retrieved 13398: 13392:"Lecture 16" 13374: 13336: 13307: 13289:the original 13274: 13250: 13227: 13194: 13172: 13158:Bibliography 13143: 13131: 13119: 13114:, p. 1. 13112:Watrous 2006 13092: 13044: 13032: 13020: 13013:Fortnow 1997 13008: 12996: 12984: 12972: 12960: 12955:, p. 6. 12948: 12943:, p. 5. 12936: 12931:, p. 7. 12894: 12889:, p. 4. 12882: 12875:Gasarch 2019 12870: 12865:, p. 3. 12858: 12846: 12834: 12822: 12810: 12798: 12633: 11979: 11975: 11971: 11967: 11962:is a strict 11959: 11957: 11947: 11942: 11940: 11803: 11663: 11613: 11606: 11604: 11549: 11546:planar graph 11543: 11310: 11205: 11204:are said to 11161: 11053: 10894: 10786: 10697: 10696: 10680: 10676: 10672: 10668: 10662: 10656: 10652: 10648: 10646: 10641: 10637: 10633: 10629: 10625: 10621: 10617: 10613: 10609: 10605: 10601: 10596: 10592: 10587: 10581: 10577: 10565: 10559: 10557: 10345: 10193: 10191: 9837: 9830: 9826: 9822: 9818: 9810: 9806: 9798: 9797:And just as 9796: 9603: 9596: 9588: 9584: 9580: 9579: 9549: 9286: 9261: 9231:simple cycle 9206: 9178: 9177:), but asks 9170: 9166: 9164: 9134: 9122: 9112: 9106: 9105:The classes 9104: 9091: 9087:adding to it 9082: 9055: 9051: 9047: 9043: 9035: 9029: 9023: 9019: 9017: 9004: 8996: 8958: 8954: 8948: 8940: 8899: 8895: 8890: 8886: 8881: 8880: 8875: 8874:that are in 8637: 8635: 8436: 7973: 7963: 7931: 7580: 7561: 7555: 7200: 7194: 7192: 7129: 7125: 7095: 7091: 7087: 7083: 7079: 7074: 7070: 7066: 7062: 7056: 7052: 7050: 7039: 7035: 7033: 6736: 6734: 6701: 6696: 6694: 6689: 6685: 6681: 6667: 6665: 6592: 6572:cryptography 6565: 6559: 6557: 6539: 6533: 6527: 6525: 6520: 6516: 6512: 6508: 6504: 6500: 6496: 6492: 6488: 6484: 6480: 6432: 6428: 6424: 6420: 6416: 6412: 6408: 6404: 6400: 6396: 6395: 6388: 6386: 6379: 6375: 6367: 6363: 6357: 6351: 6342: 6338: 6332: 6268: 6262: 6260: 6255: 6249: 6247: 6240: 6234: 6228: 6222: 6216: 6214: 5925: 5910: 5908: 5894: 5887: 5881: 5869: 5863: 5857: 5845: 5839: 5833: 5821: 5815: 5809: 5803: 5789: 5779: 5775: 5771: 5767: 5765: 5616:states that 5611: 5461:states that 5456: 5181: 5179: 5160: 5155: 5151: 5147: 5143: 5141: 4913: 4892: 4888: 4884: 4880: 4876: 4872: 4866: 4863: 4858: 4834: 4810: 4804: 4780: 4776: 4775:is hard for 4754: 4751:Completeness 4742: 4738: 4734: 4690: 4666: 4662: 4638: 4636: 4608: 4569: 4487: 4384: 4345: 4157: 4155: 4099: 4095: 4091: 3913: 3846: 3841: 3837: 3831: 3766: 3762: 3758: 3756: 3751: 3729: 3714: 3710: 3706: 3702: 3698: 3694: 3693:showed that 3689: 3455: 3451: 3445: 3439: 3435: 3431: 3429: 3413: 3409: 3356: 3352: 3344: 3340: 3338: 3130: 3126: 3120: 3114: 3110: 3106: 3104: 3043: 2903: 2899: 2895: 2891: 2890: 2842: 2811: 2807: 2803: 2799: 2795: 2773: 2769: 2765: 2761: 2757: 2756: 2534: 2530: 2526: 2522: 2521: 2423: 2419: 2415: 2410: 2406: 2402: 2398: 2394: 2390: 2386: 2382: 2340: 2336: 2331: 2327: 2325: 2315: 2309: 2204: 2056: 1921: 1898: 1894: 1890: 1886: 1884: 1879: 1871: 1870: 1694: 1682: 1681: 1258: 1254: 1250: 1246: 1244: 1081: 1072:Space bounds 1054: 907: 890: 885: 883: 826: 822: 816: 806: 802: 799:upper bounds 796: 787: 778: 772: 768: 738: 730:decidability 725: 721: 691: 683: 678: 669: 667: 637: 622: 612: 602: 578: 566: 556: 487: 481: 477: 457: 427: 262: 238: 212: 198: 194: 189: 185: 170: 164: 158: 152: 146: 140: 134: 129: 125: 90: 68: 43: 37: 13813:#P-complete 13751:NP-complete 13666:NL-complete 13240:Barak, Boaz 13189:Barak, Boaz 12989:Sipser 2006 12914:Sipser 2006 12899:Sipser 2006 12839:Sipser 2006 12827:Sipser 2006 12049:Undecidable 11686:such that: 10406:satisfying 9815:certificate 7930:is said to 7611:logic gates 6678:certificate 6479:. That is, 6427:relates to 3757:Each class 3744:conjunction 3740:disjunction 3450:. That is, 3125:. That is, 2845:logarithmic 2810:must equal 2463:, and most 1926:certificate 898:Time bounds 811:grows at a 640:Blum axioms 400:linguistics 217:of related 13989:Categories 13868:ELEMENTARY 13693:P-complete 13416:October 5, 13066:Barak 2006 13025:Arora 2003 12790:References 11689:For every 9094:April 2017 8626:polynomial 7548:nodes are 7528:, and the 7524:nodes are 7500:nodes are 6666:The class 4747:problems. 4150:See also: 4146:Reductions 2271:such that 1891:verifiable 1234:See also: 1058:polynomial 813:polynomial 209:Background 56:complexity 13863:2-EXPTIME 13097:Rich 2008 12767:⁡ 12732:⁡ 12677:⁡ 12651:⁡ 12073:Decidable 11920:Π 11909:∗ 11866:Π 11839:Π 11760:Π 11756:∈ 11745:For ever 11704:Π 11700:∈ 11641:Π 11628:Π 11583:∗ 11563:∈ 11513:Π 11466:Π 11455:∗ 11412:Π 11385:Π 11362:∗ 11333:Π 11329:∪ 11320:Π 11296:∅ 11284:Π 11280:∩ 11271:Π 11244:Π 11217:Π 11186:Π 11182:∪ 11173:Π 11142:Π 11138:∪ 11129:Π 11099:Π 11086:Π 11036:∗ 11016:⊆ 11007:Π 10982:∗ 10962:⊆ 10953:Π 10941:, where: 10920:Π 10907:Π 10878:∗ 10819:∗ 10799:∈ 10731:∗ 10711:⊆ 10536:∗ 10532:Σ 10528:∈ 10429:∈ 10329:∗ 10325:Σ 10321:× 10316:∗ 10312:Σ 10308:⊆ 10282:Σ 10216:→ 10034:∈ 9980:∗ 9960:∈ 9912:→ 9876:→ 9871:∗ 9710:∗ 9690:∈ 9642:→ 9637:∗ 9564:economics 9480:∗ 9460:∈ 9430:# 9379:∗ 9359:∈ 9331:→ 9326:∗ 9293:functions 9241:# 8970:Σ 8917:≠ 8851:⊊ 8816:⊂ 8736:→ 8531:→ 7966:Languages 7711:→ 7623:NOT gates 7572:computers 7550:NOT gates 7536:¬ 7512:∨ 7502:AND gates 7488:∧ 7356:¬ 7353:∨ 7337:∧ 7318:∧ 7302:∧ 7286:¬ 7159:⊆ 7109:≥ 7007:≤ 6905:≥ 6804:∈ 6720:ϵ 6460:∩ 6183:ϵ 6180:− 6174:≥ 6104:a string 6090:ϵ 6087:− 6081:≥ 6011:a string 5995:ϵ 5935:ϵ 5725:⁡ 5719:⋅ 5675:⊊ 5571:⁡ 5558:⋅ 5517:⊊ 5432:≤ 5376:⊆ 5320:≤ 5156:NEXPSPACE 5071:⊆ 4869:-complete 4591:∈ 4554:∈ 4529:∗ 4525:Σ 4521:∈ 4367:∈ 4330:∈ 4305:∗ 4301:Σ 4297:∈ 4158:reduction 3979:∘ 3808:∈ 3803:¯ 3699:NEXPSPACE 3623:∈ 3616:⋃ 3508:∈ 3501:⋃ 3456:NEXPSPACE 3436:NEXPSPACE 3374:⊆ 3279:∈ 3272:⋃ 3177:∈ 3170:⋃ 3072:⊆ 3059:⊆ 3023:⁡ 2955:⁡ 2904:NLOGSPACE 2858:⁡ 2783:⊆ 2693:∈ 2686:⋃ 2584:∈ 2577:⋃ 2482:≠ 2441:≠ 2420:construct 2359:⊆ 2218:∈ 2150:∗ 2130:∈ 1814:∈ 1807:⋃ 1730:∈ 1723:⋃ 1133:→ 959:→ 844:⊆ 722:recognize 618:processor 524:algorithm 349:∈ 269:algorithm 13858:EXPSPACE 13853:NEXPTIME 13621:DLOGTIME 13535:Archived 13515:Archived 13466:(2006). 13453:Archived 13428:(2008). 13407:Archived 13363:Archived 13327:(2006). 13314:Archived 13259:Archived 13232:Archived 13205:Archived 13191:(2009). 13177:Archived 12965:Lee 2014 12613:See also 12121:NEXPTIME 12097:EXPSPACE 11120:is thus 10647:Just as 10636:implies 10517:for all 10486:function 10273:alphabet 10198:function 9827:how many 9262:how many 9179:how many 8697:, where 8548:, where 8276:of size 8216:, where 8047:, where 7526:OR gates 7086:, where 6971:implies 6869:implies 6773:, where 5342:, since 5152:EXPSPACE 4806:complete 4633:Hardness 3736:negation 3695:EXPSPACE 3452:EXPSPACE 3447:NEXPTIME 3432:EXPSPACE 3426:EXPSPACE 2896:LOGSPACE 2829:L and NL 2812:NEXPTIME 2796:NEXPTIME 2766:NEXPTIME 2531:NEXPTIME 2518:NEXPTIME 2306:accepts. 1668:P and NP 1150:, where 976:, where 886:inherent 829:, since 613:inherent 172:EXPSPACE 166:NEXPTIME 13848:EXPTIME 13756:NP-hard 13169:"P=?NP" 12666:, i.e. 12145:EXPTIME 11970:, then 11552:string 11162:promise 10595:versus 9207:whether 9171:whether 8957:, then 8902:, then 8889:versus 7932:compute 7560:is the 6951:not in 6124:not in 5772:EXPTIME 5148:NPSPACE 4783:, then 4744:NP-hard 3732:closure 3726:Closure 3715:EXPTIME 3441:EXPTIME 3357:NPSPACE 3131:NPSPACE 3111:NPSPACE 2808:EXPTIME 2774:EXPTIME 2758:EXPTIME 2523:EXPTIME 2514:EXPTIME 2411:at most 2339:versus 1928:string 823:EXPTIME 818:EXPTIME 384:strings 197:versus 188:equals 163:⊆ 160:EXPTIME 157:⊆ 151:⊆ 145:⊆ 139:⊆ 13955:NSPACE 13950:DSPACE 13825:PSPACE 13564:, and 13479:  13445:  13355:  13281:  13211:  12169:PSPACE 11964:subset 11924:ACCEPT 11870:REJECT 11843:ACCEPT 11764:REJECT 11708:ACCEPT 11662:is in 11645:REJECT 11632:ACCEPT 11517:ACCEPT 11470:ACCEPT 11416:REJECT 11403:(with 11389:ACCEPT 11337:REJECT 11324:ACCEPT 11288:REJECT 11275:ACCEPT 11248:REJECT 11221:ACCEPT 11190:REJECT 11177:ACCEPT 11146:REJECT 11133:ACCEPT 11103:REJECT 11090:ACCEPT 11011:REJECT 10957:ACCEPT 10924:REJECT 10911:ACCEPT 9562:, and 9498:) and 9229:has a 9147:, and 9020:P/poly 9005:P/poly 8997:P/poly 8955:P/poly 8941:P/poly 8900:P/poly 8882:P/poly 8876:P/poly 8856:P/poly 8821:P/poly 8639:P/poly 7621:, and 7504:, the 7480:. The 7447:, and 7041:PSPACE 6578:, and 6538:, and 6239:, and 5859:P/poly 5844:, and 5820:, and 5780:PSPACE 5144:PSPACE 3769:(i.e. 3709:, and 3703:PSPACE 3414:PSPACE 3353:PSPACE 3127:PSPACE 3107:PSPACE 2184:is in 1259:NSPACE 1255:DSPACE 726:decide 577:(e.g. 565:(e.g. 456:is in 177:subset 154:PSPACE 119:, and 79:memory 64:memory 13945:NTIME 13940:DTIME 13761:co-NP 13518:(PDF) 13505:(PDF) 13490:(PDF) 13473:(PDF) 13456:(PDF) 13435:(PDF) 13410:(PDF) 13395:(PDF) 13366:(PDF) 13341:(PDF) 13332:(PDF) 13317:(PDF) 13304:(PDF) 13292:(PDF) 13271:(PDF) 13247:(PDF) 13201:Draft 12625:Notes 12321:co-NP 11550:every 11537:is a 10787:every 10644:). 10620:then 10600:. If 10484:is a 9825:asks 9435:CYCLE 9246:CYCLE 9205:asks 9191:CYCLE 9036:depth 8624:is a 7645:with 7601:is a 6513:co-RP 6501:co-RP 6497:co-RP 6489:co-RP 6465:co-RP 6433:co-RP 6405:co-RP 6381:P=BPP 6343:co-RP 6334:co-RP 6230:co-RP 5182:DTIME 3838:co-NP 3833:co-NP 2806:then 2393:. If 2030:proof 1251:NTIME 1247:DTIME 1064:? An 702:PRIME 679:every 633:bytes 536:PRIME 520:prime 442:PRIME 412:PRIME 335:PRIME 311:PRIME 295:prime 235:space 46:is a 13773:TFNP 13477:ISBN 13443:ISBN 13418:2022 13353:ISBN 13279:ISBN 13209:ISBN 12758:> 12723:< 11857:and 11235:and 10765:for 9496:bits 9111:and 9028:and 6511:and 6495:and 6487:and 6431:and 6403:and 6341:and 6007:if: 5886:and 5868:and 5612:The 5457:The 5174:and 4999:> 4861:). 4809:for 4639:hard 4625:and 4617:and 4206:and 4059:> 3895:1000 3779:co-X 3763:co-X 3444:and 3434:and 3119:and 3109:and 2864:< 2837:and 2764:and 2535:NEXP 2516:and 2330:and 1693:and 1676:and 1257:and 1249:and 1082:The 1060:? A 908:The 773:The 689:"). 388:bits 231:time 215:sets 103:and 75:time 62:and 60:time 42:, a 13888:ALL 13788:QMA 13778:FNP 13720:APX 13715:BQP 13710:BPP 13700:ZPP 13631:ACC 13379:doi 13345:doi 12764:log 12729:log 12674:log 12648:log 12424:BPP 12334:BQP 11966:of 11948:SZK 11308:. 10892:. 10673:FNP 10658:FNP 10572:in 9547:. 9114:QMA 9108:BQP 9089:. 9003:". 8878:). 7615:AND 7607:bit 7202:QIP 7196:MIP 6849:in 6732:. 6690:dIP 6541:RLP 6529:BPL 6523:. 6521:ZPP 6517:and 6481:ZPP 6445:ZPP 6425:ZPP 6421:BPP 6409:BPP 6397:ZPP 6376:BPP 6368:BPP 6364:BPP 6359:BPP 6349:. 6258:. 6251:ZPP 6236:BPP 6218:ZPP 6031:in 5889:QMA 5883:BQP 5823:ZPP 5805:BPP 5722:log 5562:log 5414:if 5302:if 4629:. 3830:). 3020:log 2952:log 2855:log 2527:EXP 2008:if 1968:if 1922:and 1689:in 881:). 779:any 480:or 478:yes 299:set 251:in 233:or 123:). 77:or 66:. 50:of 48:set 38:In 13991:: 13883:RE 13873:PR 13820:IP 13808:#P 13803:PP 13798:⊕P 13793:PH 13783:AM 13746:NP 13741:UP 13725:FP 13705:RP 13683:CC 13678:SC 13673:NC 13661:NL 13656:FL 13651:RL 13646:SL 13636:TC 13626:AC 13568:: 13548:. 13513:. 13507:. 13451:. 13441:. 13437:. 13405:. 13401:. 13397:. 13361:. 13351:. 13312:. 13306:. 13257:. 13253:. 13249:. 13226:. 13203:. 13187:; 13171:. 13104:^ 13073:^ 13056:^ 12921:^ 12906:^ 12546:NC 12349:NP 11938:. 11541:. 10683:. 10681:NP 10669:FP 10664:NP 10655:, 10649:FP 10642:FP 10638:#P 10634:NP 10626:NP 10618:FP 10614:#P 10610:NP 10606:FP 10602:#P 10597:NP 10588:FP 10578:FP 10576:. 10566:FP 10561:FP 10550:. 10294:: 9994:, 9838:#P 9831:#P 9823:#P 9819:NP 9811:NP 9807:#P 9799:NP 9724:, 9604:#P 9597:#P 9589:NP 9585:NP 9581:#P 9576:♯P 9566:. 9558:, 9554:, 9393:, 9165:A 9143:, 9127:. 9062:. 9056:NC 9052:NC 9048:AC 9044:NC 9031:AC 9025:NC 9015:. 8959:PH 8953:⊆ 8950:NP 8939:. 8896:NP 8891:NP 8628:. 8134:, 7961:. 7619:OR 7617:, 7414:, 7190:. 7130:AM 7126:AM 7124:, 7096:AM 7092:AM 7084:AM 7080:AM 7075:AM 7063:IP 7058:AM 7053:IP 7036:IP 6979:Pr 6877:Pr 6738:IP 6697:NP 6686:NP 6682:NP 6669:NP 6582:. 6574:, 6567:NP 6544:. 6535:RL 6532:, 6509:RP 6505:RP 6493:RP 6485:RP 6455:RP 6429:RP 6423:. 6417:PP 6413:PP 6401:RP 6399:, 6390:PP 6339:RP 6269:RP 6264:RP 6245:. 6242:PP 6233:, 6227:, 6224:RP 6221:, 6153:Pr 6060:Pr 5923:. 5871:AC 5865:NC 5847:AM 5841:MA 5838:, 5835:IP 5817:RP 5814:, 5811:PP 5808:, 5782:. 5154:= 5146:= 5014:, 4895:. 4893:NP 4885:NP 4881:NP 4877:NP 4873:NP 4867:NP 4739:NP 4613:, 4606:. 4543:, 4382:. 4319:, 3844:. 3842:NP 3742:, 3738:, 3717:. 3707:NP 3705:, 3347:, 3345:NP 3122:NP 2900:NL 2814:. 2804:NP 2770:NP 2504:. 2416:NP 2399:NP 2387:NP 2341:NP 2332:NP 2316:NP 2164:, 2057:NP 1895:NP 1887:NP 1695:NP 1226:. 1052:. 668:A 580:#P 568:FP 482:no 472:A 460:. 458:NP 429:NP 255:. 199:NP 190:NP 148:NP 136:NL 115:, 111:, 13878:R 13688:P 13641:L 13599:e 13592:t 13585:v 13420:. 13385:. 13381:: 13347:: 13217:. 13068:. 13027:. 13015:. 12967:. 12877:. 12805:. 12782:. 12770:n 12761:c 12755:n 12735:n 12726:c 12720:n 12700:c 12680:n 12654:n 12645:c 12501:P 11980:X 11976:Y 11972:X 11968:Y 11960:X 11943:P 11915:/ 11905:} 11901:1 11898:, 11895:0 11892:{ 11835:= 11832:L 11812:L 11787:0 11784:= 11781:) 11778:x 11775:( 11772:M 11769:, 11753:x 11731:1 11728:= 11725:) 11722:x 11719:( 11716:M 11713:, 11697:x 11674:M 11664:P 11650:) 11637:, 11624:( 11614:P 11607:P 11579:} 11575:1 11572:, 11569:0 11566:{ 11560:s 11525:L 11522:= 11492:L 11461:/ 11451:} 11447:1 11444:, 11441:0 11438:{ 11358:} 11354:1 11351:, 11348:0 11345:{ 11342:= 11293:= 11108:) 11095:, 11082:( 11062:M 11032:} 11028:1 11025:, 11022:0 11019:{ 10978:} 10974:1 10971:, 10968:0 10965:{ 10929:) 10916:, 10903:( 10874:} 10870:1 10867:, 10864:0 10861:{ 10841:M 10815:} 10811:1 10808:, 10805:0 10802:{ 10796:w 10773:L 10753:M 10727:} 10723:1 10720:, 10717:0 10714:{ 10708:L 10679:= 10677:P 10671:= 10653:P 10640:= 10632:= 10630:P 10624:= 10622:P 10616:= 10604:= 10593:P 10583:P 10525:x 10505:) 10502:x 10499:( 10496:f 10472:f 10452:y 10432:R 10426:) 10423:y 10420:, 10417:x 10414:( 10394:y 10374:x 10354:f 10305:R 10259:R 10239:f 10219:B 10213:A 10210:: 10207:f 10177:. 10165:w 10145:) 10142:w 10139:( 10136:f 10114:| 10107:} 10102:1 10099:= 10096:) 10093:c 10090:, 10087:w 10084:( 10081:V 10078:: 10073:) 10069:| 10065:w 10061:| 10057:( 10054:p 10050:} 10046:1 10043:, 10040:0 10037:{ 10031:c 10026:{ 10019:| 10014:= 10011:) 10008:w 10005:( 10002:f 9976:} 9972:1 9969:, 9966:0 9963:{ 9957:w 9937:V 9916:N 9908:N 9904:: 9901:p 9880:N 9867:} 9863:1 9860:, 9857:0 9854:{ 9851:: 9848:f 9793:. 9781:w 9761:M 9741:) 9738:w 9735:( 9732:f 9706:} 9702:1 9699:, 9696:0 9693:{ 9687:w 9667:M 9646:N 9633:} 9629:1 9626:, 9623:0 9620:{ 9617:: 9614:f 9535:G 9515:) 9512:G 9509:( 9506:f 9476:} 9472:1 9469:, 9466:0 9463:{ 9457:G 9410:) 9407:w 9404:( 9401:f 9375:} 9371:1 9368:, 9365:0 9362:{ 9356:w 9335:N 9322:} 9318:1 9315:, 9312:0 9309:{ 9306:: 9303:f 9272:G 9217:G 9096:) 9092:( 8980:P 8974:2 8925:P 8922:N 8912:P 8887:P 8846:P 8810:P 8786:) 8783:) 8780:n 8777:( 8772:2 8768:t 8764:( 8761:O 8740:N 8732:N 8728:: 8725:t 8705:t 8685:) 8682:) 8679:n 8676:( 8673:t 8670:( 8665:E 8662:M 8659:I 8656:T 8653:D 8612:f 8590:n 8586:C 8565:) 8562:n 8559:( 8556:f 8535:N 8527:N 8523:: 8520:f 8500:) 8497:. 8494:. 8491:. 8488:, 8483:2 8479:C 8475:, 8470:1 8466:C 8462:, 8457:0 8453:C 8449:( 8422:w 8402:w 8380:n 8376:C 8355:) 8352:. 8349:. 8346:. 8343:, 8338:2 8334:C 8330:, 8325:1 8321:C 8317:, 8312:0 8308:C 8304:( 8284:n 8264:w 8244:w 8224:n 8204:1 8201:= 8198:) 8195:w 8192:( 8187:n 8183:C 8162:L 8142:w 8122:w 8102:L 8082:n 8060:n 8056:C 8035:) 8032:. 8029:. 8026:. 8023:, 8018:2 8014:C 8010:, 8005:1 8001:C 7997:, 7992:0 7988:C 7984:( 7947:C 7943:f 7918:C 7898:) 7893:n 7889:x 7885:, 7882:. 7879:. 7876:. 7873:, 7868:2 7864:x 7860:, 7855:1 7851:x 7847:( 7842:C 7838:f 7834:= 7831:b 7811:b 7789:n 7785:x 7781:, 7778:. 7775:. 7772:. 7769:, 7764:2 7760:x 7756:, 7751:1 7747:x 7726:} 7723:1 7720:, 7717:0 7714:{ 7706:n 7702:} 7698:1 7695:, 7692:0 7689:{ 7686:: 7681:C 7677:f 7653:n 7633:C 7589:C 7552:. 7468:0 7465:= 7460:3 7456:x 7435:1 7432:= 7427:2 7423:x 7402:0 7399:= 7394:1 7390:x 7369:) 7364:3 7360:x 7350:) 7345:3 7341:x 7332:2 7328:x 7324:( 7321:( 7315:) 7310:2 7306:x 7297:1 7293:x 7289:( 7283:= 7280:) 7275:3 7271:x 7267:, 7262:2 7258:x 7254:, 7249:1 7245:x 7241:( 7236:C 7232:f 7178:] 7175:k 7172:[ 7167:P 7164:I 7156:] 7153:k 7150:[ 7145:M 7142:A 7128:= 7112:2 7106:k 7088:k 7016:3 7013:1 7004:] 7001:P 6993:w 6985:V 6982:[ 6959:L 6939:w 6914:3 6911:2 6902:] 6899:P 6891:w 6883:V 6880:[ 6857:L 6837:w 6812:P 6809:I 6801:L 6781:V 6761:) 6758:V 6755:, 6752:P 6749:( 6645:P 6625:V 6605:P 6450:= 6319:M 6299:M 6279:M 6177:1 6171:] 6168:w 6160:M 6157:[ 6132:L 6112:w 6084:1 6078:] 6075:w 6067:M 6064:[ 6039:L 6019:w 5975:L 5955:M 5776:L 5768:P 5762:. 5748:) 5743:) 5740:) 5737:n 5734:( 5731:f 5728:( 5716:) 5713:n 5710:( 5707:f 5702:( 5695:E 5692:C 5689:A 5686:P 5683:S 5680:D 5670:) 5665:) 5662:n 5659:( 5656:f 5651:( 5644:E 5641:C 5638:A 5635:P 5632:S 5629:D 5608:. 5594:) 5589:) 5586:) 5583:n 5580:( 5577:f 5574:( 5566:2 5555:) 5552:n 5549:( 5546:f 5541:( 5534:E 5531:M 5528:I 5525:T 5522:D 5512:) 5507:) 5504:n 5501:( 5498:f 5493:( 5486:E 5483:M 5480:I 5477:T 5474:D 5440:2 5436:k 5427:1 5423:k 5402:) 5395:2 5391:k 5386:n 5382:( 5379:O 5373:) 5366:1 5362:k 5357:n 5353:( 5350:O 5328:2 5324:k 5315:1 5311:k 5290:) 5283:2 5279:k 5274:n 5270:( 5265:E 5262:M 5259:I 5256:T 5253:D 5231:) 5224:1 5220:k 5215:n 5211:( 5206:E 5203:M 5200:I 5197:T 5194:D 5127:. 5123:) 5117:2 5112:) 5109:n 5106:( 5101:f 5097:( 5091:E 5088:C 5085:A 5082:P 5079:S 5076:D 5067:) 5062:) 5059:n 5056:( 5052:f 5048:( 5042:E 5039:C 5036:A 5033:P 5030:S 5027:N 5002:n 4996:) 4993:n 4990:( 4987:f 4965:2 4961:) 4957:n 4954:( 4951:f 4931:) 4928:n 4925:( 4922:f 4889:P 4859:C 4845:X 4835:C 4821:X 4811:C 4791:X 4781:C 4777:C 4763:X 4735:C 4721:X 4701:X 4691:C 4677:X 4667:C 4663:C 4649:X 4594:Y 4588:) 4585:x 4582:( 4579:p 4557:X 4551:x 4518:x 4498:p 4474:Y 4454:X 4434:Y 4414:Y 4394:X 4370:Y 4364:) 4361:x 4358:( 4355:f 4333:X 4327:x 4294:x 4274:f 4254:Y 4234:X 4214:y 4194:x 4174:y 4171:+ 4168:x 4140:c 4126:) 4121:n 4117:c 4113:( 4110:O 4100:P 4096:P 4092:P 4078:) 4073:3 4069:n 4065:( 4062:O 4056:) 4051:6 4047:n 4043:( 4040:O 4020:) 4015:6 4011:n 4007:( 4004:O 4001:= 3998:) 3993:2 3989:n 3985:( 3982:O 3976:) 3971:3 3967:n 3963:( 3960:O 3940:) 3935:3 3931:n 3927:( 3924:O 3914:P 3900:) 3891:n 3887:( 3884:O 3864:) 3861:n 3858:( 3855:O 3840:= 3818:} 3813:X 3800:L 3794:| 3790:L 3787:{ 3784:= 3767:X 3759:X 3752:P 3711:P 3697:= 3675:) 3668:k 3664:n 3659:2 3655:( 3650:E 3647:C 3644:A 3641:P 3638:S 3635:N 3627:N 3620:k 3612:= 3607:E 3604:C 3601:A 3598:P 3595:S 3592:P 3589:X 3586:E 3583:N 3560:) 3553:k 3549:n 3544:2 3540:( 3535:E 3532:C 3529:A 3526:P 3523:S 3520:D 3512:N 3505:k 3497:= 3492:E 3489:C 3486:A 3483:P 3480:S 3477:P 3474:X 3471:E 3410:P 3394:E 3391:C 3388:A 3385:P 3382:S 3379:P 3369:P 3355:= 3343:= 3341:P 3324:) 3319:k 3315:n 3311:( 3306:E 3303:C 3300:A 3297:P 3294:S 3291:N 3283:N 3276:k 3268:= 3263:E 3260:C 3257:A 3254:P 3251:S 3248:P 3245:N 3222:) 3217:k 3213:n 3209:( 3204:E 3201:C 3198:A 3195:P 3192:S 3189:D 3181:N 3174:k 3166:= 3161:E 3158:C 3155:A 3152:P 3149:S 3146:P 3116:P 3077:P 3067:L 3064:N 3054:L 3029:) 3026:n 3017:( 3012:E 3009:C 3006:A 3003:P 3000:S 2997:N 2992:= 2987:L 2984:N 2961:) 2958:n 2949:( 2944:E 2941:C 2938:A 2935:P 2932:S 2929:D 2924:= 2919:L 2892:L 2867:n 2861:n 2802:= 2800:P 2762:P 2742:) 2735:k 2731:n 2726:2 2722:( 2717:E 2714:M 2711:I 2708:T 2705:N 2697:N 2690:k 2682:= 2677:E 2674:M 2671:I 2668:T 2665:P 2662:X 2659:E 2656:N 2633:) 2626:k 2622:n 2617:2 2613:( 2608:E 2605:M 2602:I 2599:T 2596:D 2588:N 2581:k 2573:= 2568:E 2565:M 2562:I 2559:T 2556:P 2553:X 2550:E 2490:P 2487:N 2477:P 2449:P 2446:N 2436:P 2424:P 2397:= 2395:P 2391:P 2383:P 2367:P 2364:N 2354:P 2337:P 2328:P 2294:) 2291:c 2288:, 2285:w 2282:( 2279:M 2257:) 2253:| 2249:w 2245:| 2241:( 2238:p 2234:} 2230:1 2227:, 2224:0 2221:{ 2215:c 2192:L 2172:w 2146:} 2142:1 2139:, 2136:0 2133:{ 2127:w 2107:p 2087:M 2067:L 2040:w 2016:w 1996:w 1976:w 1956:w 1936:c 1909:w 1880:P 1872:P 1856:) 1851:k 1847:n 1843:( 1838:E 1835:M 1832:I 1829:T 1826:N 1818:N 1811:k 1803:= 1798:P 1795:N 1772:) 1767:k 1763:n 1759:( 1754:E 1751:M 1748:I 1745:T 1742:D 1734:N 1727:k 1719:= 1714:P 1683:P 1640:) 1637:) 1634:n 1631:( 1628:s 1625:( 1622:O 1602:) 1599:) 1596:n 1593:( 1590:s 1587:( 1582:E 1579:C 1576:A 1573:P 1570:S 1567:N 1542:) 1539:) 1536:n 1533:( 1530:s 1527:( 1524:O 1504:) 1501:) 1498:n 1495:( 1492:s 1489:( 1484:E 1481:C 1478:A 1475:P 1472:S 1469:D 1444:) 1441:) 1438:n 1435:( 1432:t 1429:( 1426:O 1406:) 1403:) 1400:n 1397:( 1394:t 1391:( 1386:E 1383:M 1380:I 1377:T 1374:N 1349:) 1346:) 1343:n 1340:( 1337:t 1334:( 1331:O 1311:) 1308:) 1305:n 1302:( 1299:t 1296:( 1291:E 1288:M 1285:I 1282:T 1279:D 1214:n 1194:M 1174:) 1171:n 1168:( 1163:M 1159:s 1137:N 1129:N 1125:: 1120:M 1116:s 1095:M 1040:n 1020:M 1000:) 997:n 994:( 989:M 985:t 963:N 955:N 951:: 946:M 942:t 921:M 867:E 864:M 861:I 858:T 855:P 852:X 849:E 839:P 827:P 808:P 583:) 571:) 507:n 370:} 362:n 358:| 353:N 346:n 343:{ 340:= 282:n 240:P 195:P 186:P 169:⊆ 142:P 133:⊆ 130:L 92:P 20:)

Index

Class (complexity theory)

computational complexity theory
set
computational problems
complexity
time
memory
model of computation
time
memory
decision problems
Turing machine
P
polynomial time
counting problems
function problems
probabilistic Turing machines
interactive proof systems
Boolean circuits
quantum computers
L
NL
P
NP
PSPACE
EXPTIME
NEXPTIME
EXPSPACE
subset

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