Complexity Zoo

Welcome to a modified version of Complexity Zoo.

There are now 603 classes.

Created by Satoshi Hada. I will welcome any comment.

Last Updated: 2025-05-04 07:38:03 +0000

Motivation

Take for example the result MA=NEXP if and only if NEXP in P/poly. Which class do you think mentions this result? The answer is NEXP (as of April 21, 2011). Neither MA nor P/poly does. So if you visit NEXP, you can find it, otherwise, you can’t. However, those who are interested in MA or P/poly should be able to find the important result. For this purpose, given a class, this modified version displays not only the class itself but also other classes having links to the class. For example, if you visit MA, it displays not only MA but also NEXP so that you can find the result.

Complexity Ranking

This is a ranked list of complexity classes. The score of a class is the number of classes whose description has a link to the class.

RankClassDescriptionScore
1PPolynomial-Time143
2NPNondeterministic Polynomial-Time135
3BPPBounded-Error Probabilistic Polynomial-Time63
4PSPACEPolynomial-Space54
5PHPolynomial-Time Hierarchy45
6P/polyNonuniform Polynomial-Time42
7BQPBounded-Error Quantum Polynomial-Time40
8EXPExponential Time38
9PPProbabilistic Polynomial-Time36
10LLogarithmic Space33
11NLNondeterministic Logarithmic-Space27
12MAMerlin-Arthur24
13NEXPNondeterministic EXP24
14#PSharp-P or Number-P22
15QMAQuantum MA20
16AMArthur-Merlin19
17coNPComplement of NP19
18DTIME(f(n))Deterministic f(n)-Time19
19EExponential Time With Linear Exponent18
20FPFunction Polynomial-Time17
21IPInteractive Proof Systems17
22RPRandomized Polynomial-Time17
23SZKStatistical Zero Knowledge17
24AC0Unbounded Fanin Constant-Depth Circuits16
25NCNick's Class15
26NC1Level 1 of NC15
27ZPPZero-Error Probabilistic Polynomial-Time15
28DSPACE(f(n))Deterministic f(n)-Space14
29FPTFixed-Parameter Tractable14
30UPUnambiguous Polynomial-Time13
31NENondeterministic E12
32Σ2PNP With NP Oracle12
33FOFirst-Order logic11
34ModkPMod-k Polynomial-Time11
35EQPExact Quantum Polynomial-Time10
36MIPMulti-Prover Interactive Proof10
37FNPFunction NP9
38NP ∩ coNPThe intersection of NP and coNP9
39⊕PParity P9
40TC0Constant-Depth Threshold Circuits9
41BQP/mpolyBQP With Polynomial-Size Deterministic Merlin-Like Advice8
42C=PExact-Counting Polynomial-Time8
43NEENondeterministic EE8
44NP/polyNonuniform NP8
45NTIME(f(n))Nondeterministic f(n)-Time8
46PccCommunication Complexity P8
47PNP[log]P With Log NP Queries8
48Δ2PP With NP Oracle7
49DETDeterminant7
50EEDouble-Exponential Time With Linear Exponent7
51NPccCommunication Complexity NP7
52k-PBPPolynomial-Size Width-k Branching Program7
53PPAPolynomial Parity Argument7
54PPccCommunication Complexity PP7
55PTASPolynomial-Time Approximation Scheme7
56QIPQuantum IP7
57RERecursively Enumerable Languages7
58S2PSecond Level of the Symmetric Hierarchy7
59ACUnbounded Fanin Polylogarithmic-Depth Circuits6
60AC1Unbounded Fanin Log-Depth Circuits6
61AWPPAlmost WPP6
62BPEEBounded-Error Probabilistic EE6
63BPLBounded-Error Probabilistic L6
64BQP/qpolyBQP With Polynomial-Size Quantum Advice6
65coNEXPComplement of NEXP6
66LOGCFLLogarithmically Reducible to CFL6
67mPMonotone P6
68NC2Level 2 of NC6
69NPCNP-Complete6
70NPONP Optimization6
71Π2PcoNP With NP Oracle6
72RRecursive Languages6
73SBPSmall Bounded-Error Probability6
74SNPStrict NP6
75SOSecond-Order logic6
76TFNPTotal Function NP6
77W[1]Weighted Analogue of NP6
78W[t]Nondeterministic Fixed-Parameter Hierarchy6
79APAlternating P5
80APXApproximable5
81BPPccCommunication Complexity BPP5
82BPPpathThreshold BPP5
83CHCounting Hierarchy5
84coAMComplement of AM5
85coNEComplement of NE5
86coNPccComplement of NPcc5
87EHExponential-Time Hierarchy With Linear Exponent5
88FewPNP With Few Witnesses5
89LWPPLength-Dependent Wide PP5
90mNLMonotone NL5
91ModkLMod-k L5
92NC0Level 0 of NC5
93NQPNondeterministic Quantum Polynomial-Time5
94PCPolynomial-Time Over The Complex Numbers5
95PPADPolynomial Parity Argument (Directed)5
96PPPPolynomial Pigeonhole Principle5
97PRPolynomial-Time Over The Reals5
98PZKPerfect Zero Knowledge5
99QSZKQuantum Statistical Zero-Knowledge5
100RNCRandomized NC5
101SLSymmetric Logarithmic-Space5
102SPPStoic PP5
103UPPccUnrestricted Communication Analogue of PP5
104VPkValiant P Over Field k5
105ACC0AC0 With Arbitrary MOD Gates4
106AM[polylog]AM With Polylog Rounds4
107APPAmplified PP4
108BP•LBounded-Error Probabilistic L with Two Way Access to Randomness4
109CFLContext-Free Languages4
110CZKComputational Zero-Knowledge4
111FO[]Iterated First-Order logic4
112frIPFunction-Restricted IP Proof Systems4
113GapLGap Logarithmic-Space4
114MaxSNPMaximization SNP4
115mLMonotone L4
116mNC1Monotone NC14
117NISZKNon-Interactive SZK4
118NPCNP Over The Complex Numbers4
119NSPACE(f(n))Nondeterministic f(n)-Space4
120O2PSecond Level of the Oblivious Symmetric Hierarchy4
121PBPPolynomial-Size Branching Program4
122PHccCommunication Complexity PH4
123PLSPolynomial Local Search4
124P-OBDDPolynomial-Size Ordered Binary Decision Diagram4
125PostBQPBQP With Postselection4
126PRPrimitive Recursive Functions4
127P-SelP-Selective Sets4
128P#PP With #P Oracle4
129QIP[2]2-Message Quantum IP4
130QNCQuantum NC4
131QPQuasipolynomial-Time4
132RG(2)Two-turn (one-round) Refereed Games4
133RLRandomized Logarithmic-Space4
134SCSteve's Class4
135#LSharp-L4
136W[P]Weighted Circuit Satisfiability4
137WPPWide PP4
138W[SAT]Weighted Satisfiability4
139XPFixed-Parameter Tractable for Each Parameter4
140YPYour Polynomial-Time or Yaroslav-Percival4
141AC0[m]AC0 With MOD m Gates3
142AMccCommunication Complexity AM3
143AmpMPAmplifiable MP3
144AvgPAverage Polynomial-Time3
145BHBoolean Hierarchy Over NP3
146BPP/mlogBPP With Logarithmic Deterministic Merlin-Like Advice3
147BPSPACE(f(n))Bounded-Error Probabilistic f(n)-Space3
148BPTIME(f(n))Bounded-Error Probabilistic f(n)-Time3
149BQP/polyBQP With Polynomial-Size Karp-Lipton Advice3
150coC=PComplement of C=P3
151coREComplement of RE3
152coRPComplement of RP3
153DCFLDeterministic CFL3
154DiffAC0Difference #AC03
155DistNPDistributional NP3
156EEXPDouble-Exponential Time3
157ELEMENTARYFinitely Iterated Exponential Time3
158EXPSPACEExponential Space3
159FBQPFunction BQP3
160FNLFunction NL3
161FO(TC)First-order with transitive closure3
162FPTASFully Polynomial-Time Approximation Scheme3
163GapPGap Polynomial-Time3
164L/polyNonuniform Logarithmic Space3
165MAEXPExponential-Time MA3
166MaxPBMaxNP Polynomially Bounded3
167mcoNLComplement of mNL3
168MIP*MIP With Quantum Provers3
169ModPHModular Counting Hierarchy3
170MPMiddle-Bit P3
171NEEXPNondeterministic EEXP3
172NPMVNP Multiple Value3
173NPMVtNPMV Total3
174NPRNP Over The Reals3
175NPSVNP Single Value3
176NQLNondet Quasi-Linear3
177ONPOblivious NP3
178para-Parameterized Complexity3
179PccPcc in NOF model, players3
180PLProbabilistic L3
181PNPP With Oracle Access To NP3
182PostBPPccCommunication Complexity PostBPP3
183PPADSPolynomial Parity Argument (Directed, Sink)3
184P||NPP With Parallel Queries To NP3
185PPSPACEProbabilistic PSPACE3
186PromiseBPPPromise-Problem BPP3
187QAC0[m]Quantum AC0[m]3
188QACC0Quantum ACC03
189QMA(2)Quantum MA With Multiple Certificates3
190QMIPQuantum Multi-Prover Interactive Proofs3
191QNC0Quantum NC03
192QRG(2)Two-turn (one-round) Quantum Refereed Games3
193QRG(k)k-turn Quantum Refereed Games3
194RGRefereed Games3
195RG(k)k-turn Refereed Games3
196S2-EXP•PNPDon't Ask3
197SPARSESparse Languages3
198SQGShort Quantum Games3
199⊕LParity L3
200TALLYTally Languages3
201ULUnambiguous L3
202VNPkValiant NP Over Field k3
203WAPPWeak Almost-Wide PP3
204XLFixed-Parameter Logspace for Each Parameter3
205XPuniformUniform XP3
206YQP*Yaroslav BQP star3
207ZBQPStrict Quantum ZPP3
208A0PPOne-Sided Analog of AWPP2
209ALAlternating L2
210ALLThe Class of All Languages2
211Almost-PLanguages Almost Surely in PA2
212AW[SAT]Alternating W[SAT]2
213AW[*]Alternating W[*]2
214AxPApproximable in Polynomial Time2
215βPLimited-Nondeterminism NP2
216BPd(P)Polynomial Size d-Times-Only Branching Program2
217BPEBounded-Error Probabilistic E2
218BPHSPACE(f(n))Bounded-Error Halting Probabilistic f(n)-Space2
219BPPccBPPcc in NOF model, players2
220BPP-OBDDPolynomial-Size Bounded-Error Ordered Binary Decision Diagram2
221BPP/rlogBPP With Logarithmic Probabilistically Sampled Random Advice2
222BQP/mlogBQP With Logarithmic-Size Deterministic Merlin-Like Advice2
223BQP/qlogBQP With Logarithmic-Size Quantum Advice2
224CheckCheckable Languages2
225CohCoherent Languages2
226compNPCompetitive NP Proof System2
227coNLComplement of NL2
228coUPComplement of UP2
229CPContinuous P2
230DQPDynamical Quantum Polynomial-Time2
231k-EQBPWidth-k Polynomial-Time Exact Quantum Branching Programs2
232ESPACEExponential Space With Linear Exponent2
233∃BPPBPP With Existential Operator2
234FewFewP With Flexible Acceptance Mechanism2
235FO(LFP)First-order with least fixed point2
236FOLLFirst-Order log log n2
237FO(PFP)First-order with partial fixed point2
238GAGraph Automorphism2
239GapAC0Gap #AC02
240GIGraph Isomorphism2
241GPCD(r(n),q(n))Generalized Probabilistically Checkable Debate2
242HeurDTIME(f(n))Heuristic DTIME2
243IC[log,poly]Logarithmic Instance Complexity, Polynomial Time2
244LkPLow Hierarchy In NP2
245LOGNPLogarithmically-Restricted NP2
246LOGSNPLogarithmically-Restricted SNP2
247MAC0Majority of AC02
248MAEExponential-Time MA With Linear Exponent2
249MaxNPMaximization NP2
250MMSNPMonadic Monotone SNP2
251mNPMonotone NP2
252NAuxPDApNondeterministic Auxiliary Pushdown Automata2
253NEXP/polyNonuniform NEXP2
254NL/polyNonuniform NL2
255NPINP-Intermediate2
256NPccNPcc in NOF model, players2
257NPOPBNPO Polynomially Bounded2
258(NP,P-samplable)Average NP With Samplable Distributions2
259NPSPACENondeterministic PSPACE2
260NPSVtNPSV Total2
261PCD(r(n),q(n))Probabilistically Checkable Debate2
262PCP(r(n),q(n))Probabilistically Checkable Proof2
263PDQPProduct Dynamical Quantum Polynomial time2
264P/logP With Logarithmic Advice2
265PNPccCommunication Complexity PNP2
266PPPP With PP Oracle2
267PromisePPromise-Problem P2
268PT1Polynomial Threshold Functions2
269QQuasi-Realtime Languages2
270QAC0Quantum AC02
271QACf0QAC0 With Fanout2
272QLQuasi-Linear2
273QMA-plusQMA With Super-Verifier2
274QMA/qpolyQMA With Polynomial-Size Quantum Advice2
275QMIPneQuantum Multi-Prover Interactive Proofs With No Prior Entanglement2
276QNCf0Quantum NC0 With Unbounded Fanout2
277QPHQuantum PH2
278QRGQuantum Refereed Games2
279QRG(1)One-turn Quantum Refereed Games2
280QRLQuantum Regular Languages2
281RBQPStrict Quantum RP2
282REGRegular Languages2
283RG(1)One-turn Refereed Games2
284RPccRandomized Pcc2
285RQPOne-sided Error Extension of EQP2
286SACSemi-Unbounded-Fanin AC2
287SAC1Semi-Unbounded-Fanin AC12
288SAPTIMEStochastic Alternating Polynomial-Time2
289SBPccCommunication Complexity SBP2
290⊕PccCommunication Complexity ⊕P2
291#AC0Sharp-AC02
292TCThreshold Circuits2
293TOWERIterated Exponential Time2
294UCFLUnambiguous CFL2
295UL/polyNonuniform UL2
296XNLFixed-Parameter Nondeterministic Logspace for Each Parameter2
297YP*Yaroslav-Percival Star2
298YPPYaroslav BPP2
299YQPYaroslav BQP2
300ZKZero-Knowledge (see CZK)2
301ZP•LZero-Error Probabilistic L with Two Way Access to Randomness2
302ZQPZero-Error Extension Of EQP2
303AHArithmetic Hierarchy1
304ALOGTIMELogarithmic time alternating RAM1
305AMEXPExponential-Time AM1
306AUC-SPACE(f(n))Randomized Alternating f(n)-Space1
307AVBPPAverage-Case BPP1
308AW[P]Alternating W[P]1
309AW[t]Alternating W[t]1
310AxPPApproximable in Probabilistic Polynomial Time1
311BPPKTBPP With Time-Bounded Kolmogorov Complexity Oracle1
312BPP/logBPP With Logarithmic Karp-Lipton Advice1
313BPP//logBPP With Logarithmic Randomness-Dependent Advice1
314BPQPBounded-Error Probabilistic QP1
315BQP/logBQP With Logarithmic-Size Karp-Lipton Advice1
316BQP-OBDDPolynomial-Size Bounded-Error Quantum Ordered Binary Decision Diagram1
317BQTIME(f(n))Bounded-Error Quantum f(n)-Time1
318CC0Constant-Depth MODm Circuits1
319C=AC0Exact-Counting AC01
320C=LExact-Counting L1
321CkPkth Level of CH1
322CLCatalytic Logspace1
323CLOGContinuous Logarithmic-Time1
324CNPContinuous NP1
325cofrIPComplement of frIP1
326compIPCompetitive IP Proof System1
327coNQPComplement of NQP1
328coRNCComplement of RNC1
329coSLComplement of SL1
330coSPARSEComplement of SPARSE1
331CSIZE(f(n))Circuit Size f(n)1
332CSLContext Sensitive Languages1
333CSPConstraint Satisfaction Problems1
334CSPACECatalytic space1
335δ-BPPδ-Semi-Random BPP1
336DP or DpDifference Polynomial-Time1
337DTISP(t(n),s(n))Simultaneous t(n)-Time and s(n)-Space1
338Dyn-FODynamic FO1
339Dyn-ThC0Dynamic Threshold Circuits1
340EEETriple-Exponential Time With Linear Exponent1
341EESPACEDouble-Exponential Space With Linear Exponent1
342EPNP with 2k Accepting Paths1
343EPTASEfficient Polynomial-Time Approximation Scheme1
344EQPKExact Quantum Polynomial-Time with Gate Set K1
345FERTFixed Error Randomized Time1
346FO(DTC)First-order with deterministic transitive closure1
347FPERTFixed Parameter and Error Randomized Time1
348FPRFixed-Parameter Randomized1
349FPRASFully Polynomial Randomized Approximation Scheme1
350FPTnuFixed-Parameter Tractable (nonuniform)1
351FPTsuFixed-Parameter Tractable (strongly uniform)1
352F-TAPE(f(n))Provable DSPACE(f(n)) For Formal System F1
353F-TIME(f(n))Provable DTIME(f(n)) For Formal System F1
354GAN-SPACE(f(n))Games Against Nature f(n)-Space1
355GCSLGrowing CSL1
356HeurBPPHeuristic BPP1
357HeurBPTIME(f(n))Heuristic BPTIME(f(n))1
358HeurPHeuristic P1
359HkPHigh Hierarchy In NP1
360HVPZKHonest-Verifier PZK1
361HVSZKHonest-Verifier SZK1
362IPPUnbounded IP1
363LC0Unbounded Fanin Linear Size (gates) Constant-Depth Circuits1
364LINLinear Time1
365LogFewLogspace-Bounded Few1
366LogFewNLLogspace-Bounded FewP1
367MAccCommunication Complexity MA1
368mALMonotone AL1
369MAPOLYLOGMA With Polylog Verifier1
370MaxSNP0Generating Class of MaxSNP1
371MinPBMinNP Polynomially Bounded1
372MIPEXPExponential-Time Multi-Prover Interactive Proof1
373ModPModkP With Arbitrary k1
374ModZkLRestricted ModkL1
375mP/polyMonotone P/poly1
376mTC0Monotone TC01
377NE/polyNonuniform NE1
378NIPZKNon-Interactive PZK1
379NISZKhNISZK With Limited Help1
380NLINNondeterministic LIN1
381NLTNearly Linear Time1
382NNLTNondeterministic Nearly Linear Time1
383NTNear-Testable1
384NT*Near-Testable With Forest Ordering1
385OMAOblivious MA1
386OptPOptimum Polynomial-Time1
387PAC0Probabilistic AC01
388para-NLParameterized Nondeterministic Logspace1
389para-NL[f log]Parameterized Nondeterministic Logspace1
390PermUPSelf-Permuting UP1
391PINCPolynomial Ignorance of Names of Classes1
392PIOPolynomial Input Output1
393PKP With Kolmogorov-Complexity Oracle1
394PKCPerfect Knowledge Complexity1
395PL1Polynomially-Bounded L1 Spectral Norm1
396PLPolynomially-Bounded L-1 Spectral Norm1
397P-LOCALPolylogarithmic rounds in the LOCAL model1
398PNP[k]P With k NP Queries(for constant k)1
399polyLPolylogarithmic Space1
400PostBPPBPP With Postselection1
401P||QMAP With Parallel Queries To QMA1
402PQMA[log]P With Log QMA Queries1
403PrHSPACE(f(n))Unbounded-Error Halting Probabilistic f(n)-Space1
404P-RLOCALPolylogarithmic rounds in the Randomized LOCAL model1
405PromiseRPPromise-Problem RP1
406PromiseUPPromise-Problem UP1
407PrSPACE(f(n))Unbounded-Error Probabilistic f(n)-Space1
408P#P[1]P With Single Query To #P Oracle1
409PSPACE/polyPSPACE With Polynomial-Size Advice1
410PT/WK(f(n),g(n))Parallel Time f(n) / Work g(n)1
411QCFLQuantum CFL1
412QCMAQuantum Classical MA1
413QCPHQuantum Classical PH1
414QHQuery Hierarchy Over NP1
415QMA+QMA With Non-Negative Amplitudes1
416QMAlogQMA With Logarithmic-Size Proofs1
417QMIPleQuantum Multi-Prover Interactive Proofs With Limited Prior Entanglement1
418QNC0/🐱Quantum NC0 With Polynomial-Size Quantum Advice1
419QNC0/qpolyQuantum NC0 With Polynomial-Size Quantum Advice1
420QPLINLinear Quasipolynomial-Time1
421RevSPACE(f(n))Reversible f(n)-Space1
422RHLRandomized Halting Logarithmic-Space1
423RHSPACE(f(n))One-Sided Error Halting Probabilistic f(n)-Space1
424RNC1Randomized NC11
425RSPACE(f(n))Randomized f(n)-Space1
426SBQPSmall Bounded-Error Quantum Polynomial-Time1
427SEHStrong Exponential Hierarchy1
428SelfNPSelf-Witnessing NP1
429SIZE(f(n))Circuit Size f(n)1
430SExclusive Stochastic Languages1
431SO(Krom)Second-order in Krom form1
432SO[LFP]Second-Order logic with least fixed point1
433SO[TC]Second-Order logic with transitive closure1
434SZKhSZK With Limited Help1
4352-EXPDouble-Exponential Time1
436⊕SAC1AC1 With Unbounded Parity Gates1
437#L/polyNonuniform #L1
438TC1Log-depth Threshold Circuits1
439Θ2PAlternate name for PNP[log]1
440TreeBQPBQP Restricted To Tree States1
441UCCUnique Connected Component1
442UEUnambiguous Exponential-Time With Linear Exponent1
443UPccCommunication Complexity UP1
444UPostBPPccUnrestricted Communication Analogue of PostBPP1
445VCkVerification Class With A Circuit of Depth K1
446VNCkValiant NC Over Field k1
447VQPkValiant QP Over Field k1
448WAPPccCommunication Complexity WAPP1
449WHILEWhile programs and some restrictions1
450WLC0Unbounded Fanin Linear Size (wires) Constant-Depth Circuits1
451W[*]Union of W[t]'s1
452W*[t]W[t] With Parameter-Dependent Depth1
453XOR-MIP*[2,1]MIP*[2,1] With 1-Bit Proofs1
454ZPPccCommunication Complexity ZPP1
4550-1-NPCBinary Restriction of NP Over The Complex Numbers0
4561NAuxPDApOne-Way NAuxPDAp0
4573SUM-hardProblems hard for 3SUM0
458#GAGraph Automorphism0
459#W[t]Sharp-W[t]0
460⊕EXPParity EXP0
461⊕L/polyNonuniform ⊕L0
462⊕SAC0AC0 With Unbounded Parity Gates0
463AckAckermann Time0
464AlgP/polyPolynomial-Size Algebraic Circuits0
465Almost-NPLanguages Almost Surely in NPA0
466Almost-PSPACELanguages Almost Surely in PSPACEA0
467AM ∩ coAMThe intersection of AM and coAM0
468AmpP-BQPBQP Restricted To AmpP States0
469APSPACEAlternating PSPACE0
470AuxPDAAuxiliary Pushdown Automata0
471AvgEAverage Exponential-Time With Linear Exponent0
472βFOLLLimited-Nondeterminism FOLL0
473βMAC0Limited-Nondeterminism MAC00
474BC=PBounded-Error C=P0
475BP•NPProbabilistic NP0
476BQLBounded-Error Quantum Logspace0
477BQNCAlternate Name for QNC0
478BQNPAlternate Name for QMA0
479BQPSPACEBounded-Error Quantum PSPACE0
480BQPtt/polyBQP/mpoly With Truth-Table Queries0
481k-BWBPBounded-Width Branching Program0
482CCComparator Circuits0
483CL#PCluster Sharp-P0
484coMAComplement of MA0
485coModkPComplement of ModkP0
486coNPCcoNP-Complete0
487coNP/polyComplement of NP/poly0
488coUCCComplement of UCC0
489cq-Σ2Classical-Quantum-Σ2P0
490D#PAlternate Name for P#P0
491δ-RPδ-Semi-Random RP0
492DistributionPHDistribution PH0
493DisNPDisjoint NP Pairs0
494DQC1Deterministic Quantum Computing with 1 Clean Bit0
495ELkPExtended Low Hierarchy0
496EQTIME(f(n))Exact Quantum f(n)-Time0
497∃NISZKNISZK With Existential Operator0
498∃RExistential theory of the reals0
499EXP/polyExponential Time With Polynomial-Size Advice0
500FBPPFunction BPP0
501FewEXPNEXP With Few Witnesses0
502FHFourier Hierarchy0
503FIXPFixed Point0
504FNL/polyNonuniform FNL0
505FPNP[log]FP With Logarithmically Many Queries To NP0
506FPLFixed Parameter Linear0
507FQMAFunction QMA0
508GC(s(n),C)Guess and Check0
509GLOGuaranteed Local Optima0
510G[t]Stratification of Fixed-Parameter Tractable Problems0
511HalfPRP With Exactly Half Acceptance0
512HeurPPHeuristic PP0
513HeurNTIME(f(n))Heuristic NTIME0
514HOHigh-Order logic0
515IOPInteractive Oracle Proof0
516IP[polylog]IP With Polylog Rounds0
517KFeasibly recursive functions0
518LHLogarithmic Time Hierarchy0
519LOGLOGloglog Space0
520MA'Sparse MA0
521MIPnsMIP with Non-Signaling Provers0
522(Mk)PAcceptance Mechanism by Monoid Mk0
523MMProblems reducible to matrix multiplication0
524ModLModL0
525MPCMonotone Planar Circuits0
526naCQPnon-adaptive Collapse-free Quantum Polynomial time0
527Nearly-PLanguages Superpolynomially Close to P0
528NEEENondeterministic EEE0
529NIQSZKNon-Interactive QSZK0
530NLONL Optimization Problems0
531NLOGNL With Nondeterministic Oracle Tape0
532NMCLNondeterministic Moore-Crutchfield Languages0
533NONEThe Empty Class0
534(NP ∩ coNP)/polyNonuniform NP ∩ coNP0
535NP/logNP With Logarithmic Advice0
536NPMV-selNPMV Selective0
537NPMVt-selNPMVt Selective0
538NPSV-selNPSV Selective0
539NPSVt-selNPSVt Selective0
540NQLNondeterministic Quantum Languages0
541OIPOblivious IP0
542PCTCP With Closed Time Curves0
543para-LParameterized Logspace0
544para-PParameterized Polynomial time.0
545P-CloseProblems Close to P0
546PEXPProbabilistic Exponential-Time0
547PFAlternate Name for FP0
548PFCHK(t(n))Proof-Checker0
549Φ2PSecond Level of the Symmetric Hierarchy, Alternative Definition0
550PhPPhysical Polynomial-Time0
551PLFPolynomial Leaf0
552PLLPolynomial Local Lemma0
553PNP[log^2]P With Log2 NP Queries0
554PODNPolynomial Odd Degree Node0
555PP/polyNonuniform PP0
556PQPProbabilistic Quantum Polynomial-Time0
557PQUERYPSPACE With Polynomial Queries0
558PromiseBQPPromise-Problem BQP0
559PSKPolynomial Sink0
560PSPACEccCommunication Complexity PSPACE0
561PTAPEArchaic for PSPACE0
562PureSuperQMAA pure-state analog of SuperQMA0
563QAMQuantum AM0
564QEPHEntangled Quantum PH0
565QMA1One Sided QMA0
566QMA+(2)QMA(2) With Non-Negative Amplitudes0
567QMAMQuantum Merlin-Arthur-Merlin Public-Coin Interactive Proofs0
568QNC1Quantum NC10
569QPIPQuantum Prover Interactive Proof0
570QPSPACEQuasipolynomial-Space0
571RPccCommunication Complexity RP0
572RPPRestricted Pseudo Polynomial-Time0
573S2ESecond Level of the Symmetric Linear Exponent Hierarchy0
574SAC0Semi-Unbounded-Fanin AC00
575SESubexponentially-Solvable Search Problems0
576SFkWidth-k Bottleneck Turing Machines0
577SKCStatistical Knowledge Complexity0
578SLICEWISE PSPACEParametrized PSPACE0
579SO(Horn)Second-order in Horn form0
580SO[]Iterated Second-Order logic0
581SPSemi-Efficient Parallel0
582span-LSpan Logarithmic-Space0
583span-PSpan Polynomial-Time0
584SPLStoic PL0
585StoqMAStoquastic MA0
586SUBEXPDeterministic Subexponential-Time0
587symPAlternate Name for S2P0
588TC0(FOLL)Languages that are TC0 Turing reducible to FOLL0
589TITensor Isomorphism0
590TREE-REGULARRegular Tree-Valued Languages0
591UAMccUnambiguous Arthur-Merlin Communication Complexity0
592UAPUnambiguous Alternating Polynomial-Time0
593USUnique Polynomial-Time0
594USBPccUnrestricted Communication Analogue of SBP0
595UWAPPccUnrestricted Communication Analogue of WAPP0
596VCorVerification Class With OR0
597VPLVisibly pushdown languages0
598XNLPFixed-Parameter Nondeterministic Logspace and Polytime for Each Parameter0
599YACCYet Another Complexity Class0
600YQP*/polyYQP* With Polynomial-Size Advice0
601ZAMccZero-Information Arthur-Merlin Communication Complexity0
602ZPEZero-Error Probabilistic E0
603ZPTIME(f(n))Zero-Error Probabilistic f(n)-Time0