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P (complexity)

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896: 456: 448: 1070:, in a 1910 paper, analyzed two algorithms for solving quadratic congruences, and observed that one took time "proportional to a power of the logarithm of the modulus" and contrasted this with one that took time proportional "to the modulus itself or its square root", thus explicitly drawing a distinction between an algorithm that ran in polynomial time versus one that ran in (moderately) exponential time. 939:
Polynomial-time algorithms are closed under composition. Intuitively, this says that if one writes a function that is polynomial-time assuming that function calls are constant-time, and if those called functions themselves require polynomial time, then the entire algorithm takes polynomial time. One
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also invented the notion independently and around the same time (Rabin's paper was in a 1967 proceedings of a 1966 conference, while Cobham's was in a 1965 proceedings of a 1964 conference and Edmonds's was published in a journal in 1965, though Rabin makes no mention of either and was apparently
828: 506:. Equivalently, it is the class of decision problems where each "yes" instance has a polynomial size certificate, and certificates can be checked by a polynomial time deterministic Turing machine. The class of problems for which this is true for the "no" instances is called 864:
is given that depends only on the length of the input. Unlike for NP, however, the polynomial-time machine doesn't need to detect fraudulent advice strings; it is not a verifier. P/poly is a large class containing nearly all practical problems, including all of
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time, because this is the total number of possible configurations; thus, L is a subset of P. Another important problem is whether L = P. We do know that P = AL, the set of problems solvable in logarithmic memory by
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P is strictly contained in EXPTIME. Consequently, all EXPTIME-hard problems lie outside P, and at least one of the containments to the right of P above is strict (in fact, it is widely believed that all three are
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instance in polynomial time automatically gives a polynomial algorithm for the corresponding decision problem). In that case P is not a subset of NP, but P∩DEC is, where DEC is the class of decision problems.
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Mathematics of computation, 1943–1993: a half-century of computational mathematics: Mathematics of Computation 50th Anniversary Symposium, August 9–13, 1993, Vancouver, British Columbia
700: 228: 948:, that can be simulated in polynomial time can simply be composed with the main polynomial-time algorithm to reduce it to a polynomial-time algorithm on a more basic machine. 999:
that there is a polynomial-time algorithm for determining if a given graph can be embedded on a torus, despite the fact that no concrete algorithm is known for this problem.
384: 322: 636: 255: 1495:(1910–1912). "The determination of the exponent to which a number belongs, the practical solution of certain congruences, and the law of quadratic reciprocity". 1023:
operator added to it, on ordered structures. In Immerman's 1999 textbook on descriptive complexity, Immerman ascribes this result to Vardi and to Immerman.
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P can also be defined as an algorithmic complexity class for problems that are not decision problems (even though, for example, finding the solution to a
885: 823:{\displaystyle {\mathsf {L}}\subseteq {\mathsf {AL}}={\mathsf {P}}\subseteq {\mathsf {NP}}\subseteq {\mathsf {PSPACE}}\subseteq {\mathsf {EXPTIME}}.} 75:". This is inexact: in practice, some problems not known to be in P have practical solutions, and some that are in P do not, but this is a useful 991:
that characterizes (for example) the set of graphs that can be embedded on a torus; moreover, Robertson and Seymour showed that there is an O(
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for itself. This is also one of the main reasons that P is considered to be a machine-independent class; any machine "feature", such as
860:, or Nonuniform Polynomial-Time. If a problem is in P/poly, then it can be solved in deterministic polynomial time provided that an 1200: 983:
Some problems are known to be solvable in polynomial time, but no concrete algorithm is known for solving them. For example, the
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is the class of problems solvable in exponential time. Of all the classes shown above, only two strict containments are known:
1660: 1638: 1526: 1410: 1385: 1344: 1268: 1118: 600: 554: 513: 1238: 2083: 1619: 1146: 510:. P is trivially a subset of NP and of co-NP; most experts believe it is a proper subset, although this belief (the 1714: 711:, the class of problems decidable in polynomial space. Again, whether P = PSPACE is an open problem. To summarize: 499: 154: 20: 1062:
unaware of them). Cobham invented the class as a robust way of characterizing efficient algorithms, leading to
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collapses to the second level. On the other hand, it also contains some impractical problems, including some
641: 1027: 50: 2118: 1707: 1570: 1444: 1050: 390: 2099: 1906: 1610: 704: 205: 551:. Another open problem is whether NP = co-NP; since P = co-P, a negative answer would imply 1626: 1067: 952: 1087: 2088: 337: 275: 972: 2042: 1258: 1108: 1008: 606: 2037: 2032: 1352: 1162: 996: 2027: 1597: 1134: 870: 233: 8: 874: 861: 548: 995:) algorithm for determining whether a graph has a given graph as a minor. This yields a 71:
holds that P is the class of computational problems that are "efficiently solvable" or "
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are "generally credited with the invention of the notion of polynomial time," though
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STOC '82: Proceedings of the fourteenth annual ACM symposium on Theory of computing
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STOC '82: Proceedings of the fourteenth annual ACM symposium on Theory of computing
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Mathematical Aspects of Computer Science. Proc. 1966 Sympos. Appl. Math., Vol. XIX
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P is known to contain many natural problems, including the decision versions of
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Mathematical Aspects of Computer Science. Proc. Sympos. Appl. Math., Vol. XIX
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Immerman, Neil (1982). "Relational Queries Computable in Polynomial Time".
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Vardi, Moshe Y. (1982). "The Complexity of Relational Query Languages".
1991: 1816: 1228: 1191: 881: 850: 436: 409:. In 2002, it was shown that the problem of determining if a number is 54: 978: 1986: 1699: 596: 1981: 1976: 1921: 1744: 1521:. Providence, RI: American Mathematical Society. pp. 503–504. 94:
is in P if and only if there exists a deterministic Turing machine
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Logic, Methodology and Philos. Sci. (Proc. 1964 Internat. Congr.)
1196:"Sparse Hard Sets for P: Resolution of a Conjecture of Hartmanis" 1012: 834: 2078: 2073: 1948: 1931: 1573:(1965). "The intrinsic computational difficulty of functions". 1447:(1965). "The intrinsic computational difficulty of functions". 920: 857: 708: 484: 476: 1026:
It was published in 2001 that PTIME corresponds to (positive)
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Hopcroft, John E.; Rajeev Motwani; Jeffrey D. Ullman (2001).
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Proc. Logic, Methodology, and Philosophy of Science II 1964
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Introduction to automata theory, languages, and computation
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http://mjn.host.cs.st-andrews.ac.uk/publications/2001d.pdf
1911: 1843: 1838: 1759: 1749: 1233:(2. ed.). Boston: Addison-Wesley. pp. 425–426. 928: 912: 451:
A representation of the relation among complexity classes
1622:. Section 34.1: Polynomial time, pp. 971–979. 923:. It is unknown if any of these containments are strict. 424:
Several natural problems are complete for P, including
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Introduction to the Theory of Computation, 2nd Edition
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such as the unary version of any undecidable problem.
581:{\displaystyle {\mathsf {P}}\subsetneq {\mathsf {NP}}} 540:{\displaystyle {\mathsf {P}}\subsetneq {\mathsf {NP}}} 720: 644: 609: 557: 516: 389:
The circuit definition can be weakened to use only a
340: 278: 236: 208: 157: 1133: 1097: 1011:, P can be described as the problems expressible in 1614:, Second Edition. MIT Press and McGraw–Hill, 2001. 979:
Pure existence proofs of polynomial-time algorithms
931:, it is unknown whether the containment is strict. 899:
P in relation to probabilistic complexity classes (
1667:Section 7.2: The Class P, pp. 256–263;. 822: 694: 630: 580: 539: 378: 316: 249: 222: 190: 442: 2110: 1491: 1002: 1334: 1086:Manindra Agrawal, Neeraj Kayal, Nitin Saxena, " 951:Languages in P are also closed under reversal, 393:family without changing the complexity class. 1715: 1625: 1328: 16:Class of problems solvable in polynomial time 1190: 185: 158: 139:P can also be viewed as a uniform family of 1585:(1967). "Mathematical theory of automata". 1429:(1967). "Mathematical theory of automata". 1358: 591:P is also known to be at least as large as 459:Inclusions of complexity classes including 191:{\displaystyle \{C_{n}:n\in \mathbb {N} \}} 1722: 1708: 987:guarantees that there is a finite list of 1263:. New York: Springer-Verlag. p. 66. 1213: 216: 181: 1513: 1306: 1253: 1103: 894: 454: 446: 435:) on alternating graphs. The article on 396: 1545: 1461: 1364: 1201:Journal of Computer and System Sciences 707:. P is also known to be no larger than 595:, the class of problems decidable in a 2111: 1729: 1647: 1569: 1443: 884:and D. Sivakumar, building on work by 812: 809: 806: 803: 800: 797: 794: 784: 781: 778: 775: 772: 769: 759: 756: 746: 736: 733: 723: 695:{\displaystyle 2^{O(\log n)}=n^{O(1)}} 573: 570: 560: 532: 529: 519: 439:lists further relevant problems in P. 147:is in P if and only if there exists a 105:runs for polynomial time on all inputs 1703: 1581: 1549:(1965). "Paths, trees, and flowers". 1465:(1965). "Paths, trees, and flowers". 1425: 1400: 1283: 1163:"complexity theory - Why is co-P = P" 849:The most difficult problems in P are 1589:. Amer. Math. Soc. pp. 153–175. 1433:. Amer. Math. Soc. pp. 153–175. 1337:Parsing Beyond Context-Free Grammars 1173:from the original on 14 October 2020 13: 1633:. Reading, Mass.: Addison–Wesley. 1141:. Pearson Education. p. 458. 845:L is strictly contained in PSPACE. 14: 2130: 2084:Probabilistically checkable proof 1671: 940:consequence of this is that P is 223:{\displaystyle n\in \mathbb {N} } 892:that is P-complete, then L = P. 888:, showed that if there exists a 500:non-deterministic Turing machine 1507: 1485: 1455: 1437: 1419: 1394: 1372:. Springer-Verlag. p. 35. 1094:160 (2004), no. 2, pp. 781–793. 856:Another generalization of P is 261:bits as input and outputs 1 bit 21:computational complexity theory 1300: 1277: 1247: 1222: 1194:; Sivakumar, D. (April 1999). 1184: 1155: 1127: 1080: 869:. If it contains NP, then the 687: 681: 665: 653: 625: 613: 443:Relationships to other classes 413:is in P. The related class of 367: 361: 355: 347: 305: 299: 293: 285: 1: 1539: 1113:. New York: Springer-Verlag. 1003:Alternative characterizations 934: 82: 1028:range concatenation grammars 379:{\displaystyle C_{|x|}(x)=0} 317:{\displaystyle C_{|x|}(x)=1} 51:deterministic Turing machine 7: 1137:; Schaefer, Marcus (2004). 705:alternating Turing machines 638:space cannot use more than 151:family of Boolean circuits 10: 2135: 2100:List of complexity classes 1627:Papadimitriou, Christos H. 1611:Introduction to Algorithms 1041: 2097: 2056: 2020: 1964: 1857: 1737: 1655:. Course Technology Inc. 1401:Kozen, Dexter C. (2006). 985:Robertson–Seymour theorem 631:{\displaystyle O(\log n)} 490:A generalization of P is 2089:Interactive proof system 1631:Computational complexity 1335:Laura Kallmeyer (2010). 1135:Johnsonbaugh, Richard F. 1073: 494:, which is the class of 49:that can be solved by a 1405:. Springer. p. 4. 1323:Information and Control 149:polynomial-time uniform 2043:Arithmetical hierarchy 1563:10.4153/CJM-1965-045-4 1479:10.4153/CJM-1965-045-4 1260:Descriptive Complexity 1215:10.1006/jcss.1998.1615 1110:Descriptive Complexity 1009:descriptive complexity 924: 824: 696: 632: 582: 541: 487: 452: 380: 318: 251: 224: 192: 2038:Grzegorczyk hierarchy 2033:Exponential hierarchy 1965:Considered infeasible 1497:Proc. Camb. Phil. Soc 1403:Theory of Computation 1378:10.1007/3-540-27477-4 1317:10.1145/800070.802187 1294:10.1145/800070.802186 1092:Annals of Mathematics 997:nonconstructive proof 898: 825: 697: 633: 583: 542: 458: 450: 397:Notable problems in P 381: 319: 252: 250:{\displaystyle C_{n}} 225: 193: 2028:Polynomial hierarchy 1858:Suspected infeasible 1598:Charles E. Leiserson 1325:, 68 (1986), 86–104. 1311:. pp. 147–152. 1288:. pp. 137–146. 875:undecidable problems 871:polynomial hierarchy 718: 642: 607: 555: 514: 338: 276: 234: 206: 155: 41:), is a fundamental 2057:Families of classes 1738:Considered feasible 1321:Revised version in 437:P-complete problems 2119:Complexity classes 1731:Complexity classes 1493:Pocklington, H. C. 927:P is contained in 925: 820: 692: 628: 603:. A decider using 578: 537: 488: 453: 403:linear programming 376: 314: 247: 220: 188: 45:. It contains all 2106: 2105: 2048:Boolean hierarchy 2021:Class hierarchies 1662:978-0-534-95097-2 1640:978-0-201-53082-7 1583:Rabin, Michael O. 1528:978-0-8218-0291-5 1451:. pp. 24–30. 1427:Rabin, Michael O. 1412:978-1-84628-297-3 1387:978-3-540-21045-0 1370:Complexity Theory 1346:978-3-642-14846-0 1270:978-0-387-98600-5 1120:978-0-387-98600-5 1068:H. C. Pocklington 1021:least fixed point 1017:first-order logic 886:Mitsunori Ogihara 496:decision problems 415:function problems 47:decision problems 2126: 1724: 1717: 1710: 1701: 1700: 1666: 1644: 1602:Ronald L. Rivest 1594:Thomas H. Cormen 1590: 1578: 1577:. North Holland. 1566: 1551:Canadian J. Math 1533: 1532: 1515:Gautschi, Walter 1511: 1505: 1504: 1489: 1483: 1482: 1467:Canadian J. Math 1459: 1453: 1452: 1441: 1435: 1434: 1423: 1417: 1416: 1398: 1392: 1391: 1362: 1356: 1350: 1332: 1326: 1320: 1304: 1298: 1297: 1281: 1275: 1274: 1251: 1245: 1244: 1226: 1220: 1219: 1217: 1188: 1182: 1181: 1179: 1178: 1159: 1153: 1152: 1131: 1125: 1124: 1101: 1095: 1084: 1035:2-satisfiability 989:forbidden minors 829: 827: 826: 821: 816: 815: 788: 787: 763: 762: 750: 749: 740: 739: 727: 726: 701: 699: 698: 693: 691: 690: 669: 668: 637: 635: 634: 629: 587: 585: 584: 579: 577: 576: 564: 563: 549:remains unproven 546: 544: 543: 538: 536: 535: 523: 522: 407:maximum matching 405:, and finding a 391:logspace uniform 385: 383: 382: 377: 360: 359: 358: 350: 323: 321: 320: 315: 298: 297: 296: 288: 256: 254: 253: 248: 246: 245: 229: 227: 226: 221: 219: 197: 195: 194: 189: 184: 170: 169: 141:Boolean circuits 59:computation time 43:complexity class 27:, also known as 2134: 2133: 2129: 2128: 2127: 2125: 2124: 2123: 2109: 2108: 2107: 2102: 2093: 2052: 2016: 1960: 1954:PSPACE-complete 1853: 1733: 1728: 1674: 1663: 1649:Sipser, Michael 1641: 1542: 1537: 1536: 1529: 1512: 1508: 1490: 1486: 1460: 1456: 1442: 1438: 1424: 1420: 1413: 1399: 1395: 1388: 1363: 1359: 1347: 1333: 1329: 1305: 1301: 1282: 1278: 1271: 1252: 1248: 1241: 1227: 1223: 1189: 1185: 1176: 1174: 1161: 1160: 1156: 1149: 1132: 1128: 1121: 1102: 1098: 1085: 1081: 1076: 1064:Cobham's thesis 1044: 1005: 981: 973:complementation 937: 890:sparse language 793: 792: 768: 767: 755: 754: 745: 744: 732: 731: 722: 721: 719: 716: 715: 677: 673: 649: 645: 643: 640: 639: 608: 605: 604: 569: 568: 559: 558: 556: 553: 552: 528: 527: 518: 517: 515: 512: 511: 504:polynomial time 498:decidable by a 445: 399: 354: 346: 345: 341: 339: 336: 335: 292: 284: 283: 279: 277: 274: 273: 241: 237: 235: 232: 231: 215: 207: 204: 203: 180: 165: 161: 156: 153: 152: 85: 69:Cobham's thesis 63:polynomial time 17: 12: 11: 5: 2132: 2122: 2121: 2104: 2103: 2098: 2095: 2094: 2092: 2091: 2086: 2081: 2076: 2071: 2066: 2060: 2058: 2054: 2053: 2051: 2050: 2045: 2040: 2035: 2030: 2024: 2022: 2018: 2017: 2015: 2014: 2009: 2004: 1999: 1994: 1989: 1984: 1979: 1974: 1968: 1966: 1962: 1961: 1959: 1958: 1957: 1956: 1946: 1941: 1940: 1939: 1929: 1924: 1919: 1914: 1909: 1904: 1899: 1894: 1893: 1892: 1890:co-NP-complete 1887: 1882: 1877: 1867: 1861: 1859: 1855: 1854: 1852: 1851: 1846: 1841: 1836: 1831: 1826: 1821: 1820: 1819: 1809: 1804: 1799: 1794: 1793: 1792: 1782: 1777: 1772: 1767: 1762: 1757: 1752: 1747: 1741: 1739: 1735: 1734: 1727: 1726: 1719: 1712: 1704: 1698: 1697: 1690:Complexity Zoo 1686: 1679:Complexity Zoo 1673: 1672:External links 1670: 1669: 1668: 1661: 1645: 1639: 1623: 1606:Clifford Stein 1591: 1579: 1567: 1541: 1538: 1535: 1534: 1527: 1506: 1484: 1454: 1436: 1418: 1411: 1393: 1386: 1357: 1345: 1327: 1299: 1276: 1269: 1255:Immerman, Neil 1246: 1240:978-0201441246 1239: 1221: 1208:(2): 280–296. 1183: 1167:Stack Overflow 1154: 1147: 1126: 1119: 1105:Immerman, Neil 1096: 1088:PRIMES is in P 1078: 1077: 1075: 1072: 1043: 1040: 1004: 1001: 980: 977: 965:Kleene closure 936: 933: 847: 846: 843: 831: 830: 819: 814: 811: 808: 805: 802: 799: 796: 791: 786: 783: 780: 777: 774: 771: 766: 761: 758: 753: 748: 743: 738: 735: 730: 725: 689: 686: 683: 680: 676: 672: 667: 664: 661: 658: 655: 652: 648: 627: 624: 621: 618: 615: 612: 575: 572: 567: 562: 534: 531: 526: 521: 444: 441: 398: 395: 387: 386: 375: 372: 369: 366: 363: 357: 353: 349: 344: 324: 313: 310: 307: 304: 301: 295: 291: 287: 282: 262: 244: 240: 218: 214: 211: 187: 183: 179: 176: 173: 168: 164: 160: 137: 136: 121: 106: 84: 81: 15: 9: 6: 4: 3: 2: 2131: 2120: 2117: 2116: 2114: 2101: 2096: 2090: 2087: 2085: 2082: 2080: 2077: 2075: 2072: 2070: 2067: 2065: 2062: 2061: 2059: 2055: 2049: 2046: 2044: 2041: 2039: 2036: 2034: 2031: 2029: 2026: 2025: 2023: 2019: 2013: 2010: 2008: 2005: 2003: 2000: 1998: 1995: 1993: 1990: 1988: 1985: 1983: 1980: 1978: 1975: 1973: 1970: 1969: 1967: 1963: 1955: 1952: 1951: 1950: 1947: 1945: 1942: 1938: 1935: 1934: 1933: 1930: 1928: 1925: 1923: 1920: 1918: 1915: 1913: 1910: 1908: 1905: 1903: 1900: 1898: 1895: 1891: 1888: 1886: 1883: 1881: 1878: 1876: 1873: 1872: 1871: 1868: 1866: 1863: 1862: 1860: 1856: 1850: 1847: 1845: 1842: 1840: 1837: 1835: 1832: 1830: 1827: 1825: 1822: 1818: 1815: 1814: 1813: 1810: 1808: 1805: 1803: 1800: 1798: 1795: 1791: 1788: 1787: 1786: 1783: 1781: 1778: 1776: 1773: 1771: 1768: 1766: 1763: 1761: 1758: 1756: 1753: 1751: 1748: 1746: 1743: 1742: 1740: 1736: 1732: 1725: 1720: 1718: 1713: 1711: 1706: 1705: 1702: 1696: 1692: 1691: 1687: 1685: 1681: 1680: 1676: 1675: 1664: 1658: 1654: 1650: 1646: 1642: 1636: 1632: 1628: 1624: 1621: 1620:0-262-03293-7 1617: 1613: 1612: 1607: 1603: 1599: 1595: 1592: 1588: 1584: 1580: 1576: 1572: 1568: 1564: 1560: 1556: 1552: 1548: 1544: 1543: 1530: 1524: 1520: 1516: 1510: 1502: 1498: 1494: 1488: 1480: 1476: 1472: 1468: 1464: 1458: 1450: 1446: 1440: 1432: 1428: 1422: 1414: 1408: 1404: 1397: 1389: 1383: 1379: 1375: 1371: 1367: 1366:Wegener, Ingo 1361: 1355:for the proof 1354: 1348: 1342: 1338: 1331: 1324: 1318: 1314: 1310: 1303: 1295: 1291: 1287: 1280: 1272: 1266: 1262: 1261: 1256: 1250: 1242: 1236: 1232: 1225: 1216: 1211: 1207: 1203: 1202: 1197: 1193: 1187: 1172: 1168: 1164: 1158: 1150: 1148:0-02-360692-4 1144: 1140: 1136: 1130: 1122: 1116: 1112: 1111: 1106: 1100: 1093: 1089: 1083: 1079: 1071: 1069: 1065: 1060: 1056: 1052: 1048: 1039: 1036: 1031: 1029: 1024: 1022: 1018: 1014: 1010: 1000: 998: 994: 990: 986: 976: 974: 970: 966: 962: 961:concatenation 958: 954: 949: 947: 946:random access 943: 932: 930: 922: 919:), allwithin 918: 914: 910: 906: 902: 897: 893: 891: 887: 883: 878: 876: 872: 868: 863: 862:advice string 859: 854: 852: 844: 840: 839: 838: 836: 817: 789: 764: 751: 741: 728: 714: 713: 712: 710: 706: 684: 678: 674: 670: 662: 659: 656: 650: 646: 622: 619: 616: 610: 602: 598: 594: 589: 565: 550: 524: 509: 505: 502:that runs in 501: 497: 493: 486: 482: 478: 474: 470: 466: 462: 457: 449: 440: 438: 434: 430: 429:-connectivity 428: 422: 420: 416: 412: 408: 404: 394: 392: 373: 370: 364: 351: 342: 333: 329: 325: 311: 308: 302: 289: 280: 271: 267: 263: 260: 242: 238: 212: 209: 201: 200: 199: 177: 174: 171: 166: 162: 150: 146: 143:. A language 142: 134: 130: 126: 122: 119: 115: 111: 107: 104: 101: 100: 99: 97: 93: 90: 80: 78: 77:rule of thumb 74: 70: 66: 64: 60: 56: 52: 48: 44: 40: 36: 35: 30: 26: 22: 1811: 1695:Class P/poly 1688: 1677: 1652: 1630: 1609: 1586: 1574: 1571:Cobham, Alan 1554: 1550: 1518: 1509: 1500: 1496: 1487: 1470: 1466: 1457: 1448: 1445:Cobham, Alan 1439: 1430: 1421: 1402: 1396: 1369: 1360: 1336: 1330: 1322: 1308: 1302: 1285: 1279: 1259: 1249: 1230: 1224: 1205: 1199: 1186: 1175:. Retrieved 1166: 1157: 1138: 1129: 1109: 1099: 1091: 1082: 1066:. However, 1049:states that 1045: 1032: 1025: 1006: 992: 982: 969:homomorphism 953:intersection 950: 938: 926: 879: 855: 848: 832: 601:memory space 590: 547:hypothesis) 489: 460: 433:reachability 426: 423: 400: 388: 331: 327: 269: 265: 258: 198:, such that 144: 138: 132: 128: 124: 117: 113: 109: 102: 98:, such that 95: 91: 86: 67: 38: 32: 28: 24: 18: 1937:#P-complete 1875:NP-complete 1790:NL-complete 1557:: 449–467. 1547:Edmonds, J. 1473:: 449–467. 1463:Edmonds, J. 1192:Cai, Jin-Yi 597:logarithmic 1992:ELEMENTARY 1817:P-complete 1540:References 1177:2020-10-14 1139:Algorithms 967:, inverse 935:Properties 882:Jin-Yi Cai 853:problems. 851:P-complete 599:amount of 83:Definition 57:amount of 55:polynomial 1987:2-EXPTIME 907:, co-RP, 880:In 1999, 790:⊆ 765:⊆ 752:⊆ 729:⊆ 660:⁡ 620:⁡ 566:⊊ 525:⊊ 213:∈ 178:∈ 135:outputs 0 120:outputs 1 73:tractable 2113:Category 1982:EXPSPACE 1977:NEXPTIME 1745:DLOGTIME 1651:(2006). 1629:(1994). 1517:(1994). 1368:(2005). 1257:(1999). 1171:Archived 1107:(1999). 842:strict). 326:For all 264:For all 202:For all 123:For all 108:For all 89:language 53:using a 1972:EXPTIME 1880:NP-hard 1684:Class P 1351:citing 1055:Edmonds 1042:History 1019:with a 1013:FO(LFP) 835:EXPTIME 330:not in 127:not in 2079:NSPACE 2074:DSPACE 1949:PSPACE 1659:  1637:  1618:  1604:, and 1525:  1503:: 1–5. 1409:  1384:  1343:  1267:  1237:  1145:  1117:  1051:Cobham 1015:, the 971:, and 921:PSPACE 858:P/poly 833:Here, 709:PSPACE 485:PSPACE 483:, and 477:P/poly 257:takes 2069:NTIME 2064:DTIME 1885:co-NP 1074:Notes 1059:Rabin 1047:Kozen 957:union 508:co-NP 469:co-NP 411:prime 61:, or 34:DTIME 29:PTIME 1897:TFNP 1657:ISBN 1635:ISBN 1616:ISBN 1523:ISBN 1407:ISBN 1382:ISBN 1341:ISBN 1265:ISBN 1235:ISBN 1143:ISBN 1115:ISBN 1053:and 431:(or 2012:ALL 1912:QMA 1902:FNP 1844:APX 1839:BQP 1834:BPP 1824:ZPP 1755:ACC 1559:doi 1475:doi 1374:doi 1313:doi 1290:doi 1210:doi 1090:", 1007:In 942:low 929:BQP 913:BQP 909:BPP 901:ZPP 867:BPP 657:log 617:log 473:BPP 417:is 268:in 112:in 31:or 19:In 2115:: 2007:RE 1997:PR 1944:IP 1932:#P 1927:PP 1922:⊕P 1917:PH 1907:AM 1870:NP 1865:UP 1849:FP 1829:RP 1807:CC 1802:SC 1797:NC 1785:NL 1780:FL 1775:RL 1770:SL 1760:TC 1750:AC 1693:: 1682:: 1608:. 1600:, 1596:, 1555:17 1553:. 1501:16 1499:. 1471:17 1469:. 1380:. 1206:58 1204:. 1198:. 1169:. 1165:. 1030:. 975:. 963:, 959:, 955:, 917:PP 915:, 911:, 905:RP 903:, 588:. 492:NP 481:PH 479:, 475:, 471:, 467:, 465:NP 463:, 427:st 421:. 419:FP 334:, 272:, 230:, 131:, 116:, 87:A 79:. 65:. 23:, 2002:R 1812:P 1765:L 1723:e 1716:t 1709:v 1665:. 1643:. 1565:. 1561:: 1531:. 1481:. 1477:: 1415:. 1390:. 1376:: 1349:. 1319:. 1315:: 1296:. 1292:: 1273:. 1243:. 1218:. 1212:: 1180:. 1151:. 1123:. 993:n 818:. 813:E 810:M 807:I 804:T 801:P 798:X 795:E 785:E 782:C 779:A 776:P 773:S 770:P 760:P 757:N 747:P 742:= 737:L 734:A 724:L 688:) 685:1 682:( 679:O 675:n 671:= 666:) 663:n 654:( 651:O 647:2 626:) 623:n 614:( 611:O 593:L 574:P 571:N 561:P 533:P 530:N 520:P 461:P 374:0 371:= 368:) 365:x 362:( 356:| 352:x 348:| 343:C 332:L 328:x 312:1 309:= 306:) 303:x 300:( 294:| 290:x 286:| 281:C 270:L 266:x 259:n 243:n 239:C 217:N 210:n 186:} 182:N 175:n 172:: 167:n 163:C 159:{ 145:L 133:M 129:L 125:x 118:M 114:L 110:x 103:M 96:M 92:L 39:n 37:( 25:P

Index

computational complexity theory
DTIME
complexity class
decision problems
deterministic Turing machine
polynomial
computation time
polynomial time
Cobham's thesis
tractable
rule of thumb
language
Boolean circuits
polynomial-time uniform
logspace uniform
linear programming
maximum matching
prime
function problems
FP
st-connectivity
reachability
P-complete problems


P
NP
co-NP
BPP
P/poly

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