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Feedback vertex set

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of an operating system, each directed cycle corresponds to a deadlock situation. In order to resolve all deadlocks, some blocked processes have to be aborted. A minimum feedback vertex set in this graph corresponds to a minimum number of processes that one needs to
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is the number of vertices in the graph. This algorithm actually computes a maximum induced forest, and when such a forest is obtained, its complement is a minimum feedback vertex set. The number of minimal feedback vertex sets in a graph is bounded by
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Another application is in complexity theory. Some computational problems on graphs are NP-hard in general, but can be solved in polynomial time for graphs with bounded FVS number. Some examples are graph isomorphism and the path reconfiguration
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problem, but since the feedback arc set problem and feedback vertex set problem in directed graphs are reducible to one another while preserving solution sizes, it also holds for the latter.
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Ueno, Shuichi; Kajitani, Yoji; Gotoh, Shin'ya (1988), "On the nonseparating independent set problem and feedback set problem for graphs with no vertex degree exceeding three",
367:. The problem remains NP-complete on directed graphs with maximum in-degree and out-degree two, and on directed planar graphs with maximum in-degree and out-degree three. 168: 578: 204: 119: 483:, it is NP-hard to approximate the problem to within any constant factor in polynomial time. The same hardness result was originally proven for the closely related 1088:
Becker, Ann; Geiger, Dan (1996), "Optimization of Pearl's method of conditioning and greedy-like approximation algorithms for the vertex feedback set problem.",
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Chen, Jianer; Liu, Yang; Lu, Songjian; O'Sullivan, Barry; Razgon, Igor (2008), "A fixed-parameter algorithm for the directed feedback vertex set problem",
341:). Thus, finding a minimum FVS in a graph is equivalent to finding a maximum induced forest (resp. maximum induced directed acyclic graph in the case of 1330:
Fomin, Fedor V.; Gaspers, Serge; Pyatkin, Artem; Razgon, Igor (2008), "On the minimum feedback vertex set problem: exact and enumeration algorithms.",
36:("removal" means deleting the vertex and all edges adjacent to it). Equivalently, each FVS contains at least one vertex of any cycle in the graph. The 512:- a set of edges in an undirected graph, whose removal makes the graph acyclic. The size of a smallest feedback edge set in a graph is called the 1585: 499:, the size of a minimum feedback vertex set is within a logarithmic factor of the maximum number of vertex-disjoint cycles in the given graph. 1164:
Chen, Jianer; Fomin, Fedor V.; Liu, Yang; Lu, Songjian; Villanger, Yngve (2008), "Improved algorithms for feedback vertex set problems",
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Bafna, Vineet; Berman, Piotr; Fujito, Toshihiro (1999), "A 2-approximation algorithm for the undirected feedback vertex set problem",
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is the number of vertices in the given directed graph. The parameterized versions of the directed and undirected problems are both
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Li, Deming; Liu, Yanpei (1999), "A polynomial algorithm for finding the minimum feedback vertex set of a 3-regular simple graph",
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Cao, Yixin; Chen, Jianer; Liu, Yang (2010), "On feedback vertex set: new measure and new structures", in Kaplan, Haim (ed.),
978: 941: 805: 1389: 1090: 480: 49: 605:(FAS) - a set of directed arcs whose removal makes the graph acyclic. Finding a smallest FAS is an NP-hard problem. 1302: 1122:
Proc. 12th Scandinavian Symposium and Workshops on Algorithm Theory (SWAT 2010), Bergen, Norway, June 21-23, 2010
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Proc. Symposium on Complexity of Computer Computations, IBM Thomas J. Watson Res. Center, Yorktown Heights, N.Y.
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Becker, Ann; Bar-Yehuda, Reuven; Geiger, Dan (2000), "Randomized algorithms for the loop cutset problem",
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By contrast, the directed version of the problem appears to be much harder to approximate. Under the
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Fomin, Fedor V.; Villanger, Yngve (2010), "Finding induced subgraphs via minimal triangulations",
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of the graph. The problem of finding a smallest feedback edge set is equivalent to finding a
423: 379: 375: 330: 86: 1374:, Leibniz International Proceedings in Informatics (LIPIcs), vol. 5, pp. 383–394, 518:
of the graph. In contrast to the FVS number, the circuit rank can be easily computed: it is
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Proc. 27th International Symposium on Theoretical Aspects of Computer Science (STACS 2010)
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Razgon, I. (2007), "Computing minimum directed feedback vertex set in O*(1.9977)", in
1431: 1558: 1540: 1480: 1385: 1323: 1151: 1113: 988: 974: 937: 850: 801: 1081: 786:"Beating the Random Ordering is Hard: Inapproximability of Maximum Acyclic Subgraph" 1526: 1522: 1505: 1475: 1427: 1380: 1375: 1351: 1311: 1269: 1253: 1225: 1205: 1175: 1143: 1109: 1061: 1020: 966: 929: 862: 842: 815: 793: 616: 601: 484: 472:
The best known approximation algorithm on undirected graphs is by a factor of two.
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for an alternative approximation algorithm with the same approximation ratio.
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of finding the size of a minimum feedback vertex set can be solved in time
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Proceedings of the 10th Italian Conference on Theoretical Computer Science
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Guruswami, Venkatesan; Manokaran, Rajsekar; Raghavendra, Prasad (2008).
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Karp's reduction also implies the NP-completeness of the FVS problem on
1508:(2000), "Feedback set problems", in Du, D.-Z.; Pardalos, P. M. (eds.), 1232: 846: 1532:
Computers and Intractability: A Guide to the Theory of NP-Completeness
1124:, Lecture Notes in Computer Science, vol. 6139, pp. 93–104, 831:"Approximating Minimum Feedback Sets and Multicuts in Directed Graphs" 1065: 688: 378:
four. The FVS problem can be solved in polynomial time on graphs of
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2008 49th Annual IEEE Symposium on Foundations of Computer Science
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Silberschatz, Abraham; Galvin, Peter Baer; Gagne, Greg (2008),
914:"Isomorphism for Graphs of Bounded Feedback Vertex Set Number" 40:
of a graph is the size of a smallest feedback vertex set. The
828: 783: 619:, feedback vertex sets play a prominent role in the study of 965:. Lecture Notes in Computer Science. Vol. 11646. 2019. 829:
Even, G.; (Seffi) Naor, J.; Schieber, B.; Sudan, M. (1998).
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is a set of vertices whose removal leaves a graph without
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Handbook of Combinatorial Optimization, Supplement vol. A
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three, the feedback vertex set problem can be solved in
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graphs, where the problem stays NP-hard on graphs of
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The feedback vertex set problem has applications in
655:unpublished results due to Garey and Johnson, cf. 572: 468:Existing constant-factor approximation algorithms. 321: 301: 281: 238: 218: 198: 162: 133: 113: 1463: 1010: 911: 771: 730: 700: 668: 1572: 1497: 1517:, Kluwer Academic Publishers, pp. 209–259 1369: 1295:"On independent circuits contained in a graph" 1163: 683: 461:The existence of an approximation preserving 430:, by transforming it into an instance of the 1557:(8th ed.), John Wiley & Sons. Inc, 1521: 1087: 912:Kratsch, Stefan; Schweitzer, Pascal (2010). 767: 656: 1043:Journal of Artificial Intelligence Research 1231: 1119: 742: 226:and their adjacent edges are deleted from 1479: 1379: 1345: 1285: 1129: 1103: 1055: 875: 450:. This follows from the following facts. 508:Instead of vertices, one can consider a 356:showed that the minimum FVS problem for 1450:; Moggi, Eugenio; Laura, Luigi (eds.), 1167:Journal of Computer and System Sciences 888:Silberschatz, Galvin & Gagne (2008) 1586:Computational problems in graph theory 1573: 1445: 706: 80:INSTANCE: An (undirected or directed) 50:first problems shown to be NP-complete 1417: 752: 750: 672: 1405: 1013:SIAM Journal on Discrete Mathematics 1003: 900:Festa, Pardalos & Resende (2000) 756: 465:from the vertex cover problem to it; 353: 1413:, New York: Plenum, pp. 85–103 502: 385: 42:minimum feedback vertex set problem 13: 1459:, World Scientific, pp. 70–81 747: 14: 1597: 772:Bafna, Berman & Fujito (1999) 731:Ueno, Kajitani & Gotoh (1988) 669:Ueno, Kajitani & Gotoh (1988) 481:computational hardness assumption 270: 479:, an unproven but commonly used 441: 422:In undirected graphs of maximum 206:such that, when all vertices of 1303:Canadian Journal of Mathematics 950: 905: 822: 777: 761: 609: 1381:10.4230/LIPIcs.STACS.2010.2470 959:Algorithms and Data Structures 736: 677: 662: 649: 566: 558: 550: 542: 534: 526: 348: 276: 264: 186: 178: 108: 96: 52:. It has wide applications in 1: 1498:Textbooks and survey articles 1432:10.1016/s0252-9602(17)30520-9 998: 67: 1504:Festa, P.; Pardalos, P. M.; 1481:10.1016/0012-365X(88)90226-9 1148:10.1007/978-3-642-13731-0_10 1114:10.1016/0004-3702(95)00004-6 918:Algorithm Theory - SWAT 2010 684:Fomin & Villanger (2010) 454:The APX-completeness of the 289:that remains after removing 163:{\displaystyle X\subseteq V} 144:QUESTION: Is there a subset 7: 1258:10.4007/annals.2005.162.439 1019:(3): 289–297 (electronic), 934:10.1007/978-3-642-13731-0_9 595:The analogous concept in a 573:{\displaystyle |E|-|V|+|C|} 10: 1602: 1180:10.1016/j.jcss.2008.05.002 768:Becker & Geiger (1996) 657:Garey & Johnson (1979) 446:The undirected problem is 48:problem; it was among the 38:feedback vertex set number 1555:Operating System Concepts 1420:Acta Mathematica Scientia 1356:10.1007/s00453-007-9152-0 1025:10.1137/S0895480196305124 971:10.1007/978-3-030-24766-9 916:. In Kaplan, Haim (ed.). 490: 417:fixed-parameter tractable 199:{\displaystyle |X|\leq k} 1235:; Safra, Samuel (2005), 643: 580:, where C is the set of 1210:10.1145/1411509.1411511 1091:Artificial Intelligence 876:Erdős & Pósa (1965) 588:, which can be done in 477:unique games conjecture 392:NP optimization problem 121:and a positive integer 114:{\displaystyle G=(V,E)} 1537:A1.1: GT7, p. 191 1316:10.4153/CJM-1965-035-8 743:Dinur & Safra 2005 574: 432:matroid parity problem 335:directed acyclic graph 323: 303: 283: 240: 220: 200: 164: 135: 115: 1448:Italiano, Giuseppe F. 1245:Annals of Mathematics 575: 324: 304: 284: 241: 221: 201: 165: 136: 116: 1581:NP-complete problems 1467:Discrete Mathematics 798:10.1109/FOCS.2008.51 792:. pp. 573–582. 582:connected components 522: 456:vertex cover problem 313: 293: 258: 230: 210: 174: 148: 125: 87: 1140:2010LNCS.6139...93C 926:2010LNCS.6139...81K 695:Fomin et al. (2008) 673:Li & Liu (1999) 246:, the remainder is 26:feedback vertex set 1197:Journal of the ACM 847:10.1007/PL00009191 719:Chen et al. (2008) 570: 497:Erdős–Pósa theorem 390:The corresponding 333:(resp. an induced 319: 299: 279: 236: 216: 196: 160: 131: 111: 1564:978-0-470-12872-5 1546:978-0-7167-1045-5 1527:Johnson, David S. 1523:Garey, Michael R. 1248:, Second Series, 1157:978-3-642-13730-3 1004:Research articles 980:978-3-030-24765-2 943:978-3-642-13731-0 807:978-0-7695-3436-7 623:recovery. In the 617:operating systems 510:feedback edge set 495:According to the 398:(1.7347), where 322:{\displaystyle G} 302:{\displaystyle X} 282:{\displaystyle G} 239:{\displaystyle G} 219:{\displaystyle X} 134:{\displaystyle k} 54:operating systems 1593: 1567: 1549: 1535:, W.H. Freeman, 1518: 1516: 1492: 1483: 1474:(1–3): 355–360, 1460: 1458: 1442: 1414: 1407:Karp, Richard M. 1402: 1383: 1366: 1349: 1326: 1299: 1282: 1281: 1280: 1274: 1268:, archived from 1241: 1228: 1190: 1174:(7): 1188–1198, 1160: 1133: 1116: 1107: 1084: 1066:10.1613/jair.638 1059: 1035: 993: 992: 964: 954: 948: 947: 909: 903: 897: 891: 885: 879: 873: 867: 866: 826: 820: 819: 781: 775: 765: 759: 754: 745: 740: 734: 728: 722: 716: 710: 704: 698: 692: 686: 681: 675: 666: 660: 653: 602:feedback arc set 579: 577: 576: 571: 569: 561: 553: 545: 537: 529: 503:Related concepts 485:feedback arc set 411:(1.9977), where 386:Exact algorithms 328: 326: 325: 320: 308: 306: 305: 300: 288: 286: 285: 280: 245: 243: 242: 237: 225: 223: 222: 217: 205: 203: 202: 197: 189: 181: 169: 167: 166: 161: 140: 138: 137: 132: 120: 118: 117: 112: 74:decision problem 58:database systems 1601: 1600: 1596: 1595: 1594: 1592: 1591: 1590: 1571: 1570: 1565: 1547: 1514: 1506:Resende, M.G.C. 1500: 1495: 1456: 1392: 1347:10.1.1.722.8913 1297: 1278: 1276: 1272: 1239: 1158: 1006: 1001: 996: 981: 962: 956: 955: 951: 944: 910: 906: 898: 894: 886: 882: 874: 870: 827: 823: 808: 782: 778: 766: 762: 755: 748: 741: 737: 729: 725: 717: 713: 705: 701: 693: 689: 682: 678: 667: 663: 654: 650: 646: 612: 590:polynomial time 586:spanning forest 565: 557: 549: 541: 533: 525: 523: 520: 519: 505: 493: 444: 436:linear matroids 428:polynomial time 388: 382:at most three. 351: 343:directed graphs 339:directed graphs 337:in the case of 314: 311: 310: 294: 291: 290: 259: 256: 255: 231: 228: 227: 211: 208: 207: 185: 177: 175: 172: 171: 149: 146: 145: 126: 123: 122: 88: 85: 84: 76:is as follows: 70: 12: 11: 5: 1599: 1589: 1588: 1583: 1569: 1568: 1563: 1550: 1545: 1519: 1499: 1496: 1494: 1493: 1461: 1443: 1426:(4): 375–381, 1415: 1403: 1390: 1367: 1340:(2): 293–307, 1327: 1283: 1252:(1): 439–485, 1229: 1204:(5), Art. 21, 1191: 1161: 1156: 1117: 1105:10.1.1.25.1442 1098:(1): 167–188, 1085: 1037: 1007: 1005: 1002: 1000: 997: 995: 994: 979: 949: 942: 904: 892: 880: 868: 841:(2): 151–174. 821: 806: 776: 760: 746: 735: 723: 711: 699: 687: 676: 661: 647: 645: 642: 641: 640: 636: 629: 625:wait-for graph 611: 608: 607: 606: 597:directed graph 593: 568: 564: 560: 556: 552: 548: 544: 540: 536: 532: 528: 504: 501: 492: 489: 470: 469: 466: 459: 443: 440: 387: 384: 380:maximum degree 376:maximum degree 350: 347: 329:is an induced 318: 298: 278: 275: 272: 269: 266: 263: 252: 251: 235: 215: 195: 192: 188: 184: 180: 159: 156: 153: 142: 130: 110: 107: 104: 101: 98: 95: 92: 69: 66: 20:discipline of 9: 6: 4: 3: 2: 1598: 1587: 1584: 1582: 1579: 1578: 1576: 1566: 1560: 1556: 1551: 1548: 1542: 1538: 1534: 1533: 1528: 1524: 1520: 1513: 1512: 1507: 1502: 1501: 1491: 1487: 1482: 1477: 1473: 1469: 1468: 1462: 1455: 1454: 1449: 1444: 1441: 1437: 1433: 1429: 1425: 1421: 1416: 1412: 1408: 1404: 1401: 1397: 1393: 1391:9783939897163 1387: 1382: 1377: 1373: 1368: 1365: 1361: 1357: 1353: 1348: 1343: 1339: 1335: 1334: 1328: 1325: 1321: 1317: 1313: 1309: 1305: 1304: 1296: 1292: 1288: 1284: 1275:on 2009-09-20 1271: 1267: 1263: 1259: 1255: 1251: 1247: 1246: 1238: 1234: 1230: 1227: 1223: 1219: 1215: 1211: 1207: 1203: 1199: 1198: 1192: 1189: 1185: 1181: 1177: 1173: 1169: 1168: 1162: 1159: 1153: 1149: 1145: 1141: 1137: 1132: 1127: 1123: 1118: 1115: 1111: 1106: 1101: 1097: 1093: 1092: 1086: 1083: 1079: 1075: 1071: 1067: 1063: 1058: 1053: 1049: 1045: 1044: 1038: 1034: 1030: 1026: 1022: 1018: 1014: 1009: 1008: 990: 986: 982: 976: 972: 968: 961: 960: 953: 945: 939: 935: 931: 927: 923: 919: 915: 908: 901: 896: 889: 884: 877: 872: 864: 860: 856: 852: 848: 844: 840: 836: 832: 825: 817: 813: 809: 803: 799: 795: 791: 787: 780: 773: 769: 764: 758: 753: 751: 744: 739: 732: 727: 720: 715: 708: 707:Razgon (2007) 703: 696: 691: 685: 680: 674: 670: 665: 658: 652: 648: 637: 634: 630: 626: 622: 618: 614: 613: 604: 603: 598: 594: 591: 587: 583: 562: 554: 546: 538: 530: 517: 516: 511: 507: 506: 500: 498: 488: 486: 482: 478: 473: 467: 464: 460: 457: 453: 452: 451: 449: 442:Approximation 439: 437: 433: 429: 425: 420: 418: 414: 410: 406: 401: 397: 393: 383: 381: 377: 373: 368: 366: 362: 360: 355: 346: 344: 340: 336: 332: 316: 296: 273: 267: 261: 249: 233: 213: 193: 190: 182: 157: 154: 151: 143: 128: 105: 102: 99: 93: 90: 83: 79: 78: 77: 75: 65: 64:chip design. 63: 59: 55: 51: 47: 43: 39: 35: 31: 27: 23: 19: 1554: 1531: 1510: 1471: 1465: 1452: 1423: 1419: 1410: 1371: 1337: 1333:Algorithmica 1331: 1307: 1301: 1277:, retrieved 1270:the original 1249: 1243: 1201: 1195: 1171: 1165: 1121: 1095: 1089: 1047: 1041: 1016: 1012: 958: 952: 917: 907: 895: 883: 871: 838: 835:Algorithmica 834: 824: 789: 779: 763: 738: 726: 714: 702: 690: 679: 664: 651: 635:chip design. 610:Applications 600: 515:circuit rank 513: 509: 494: 474: 471: 448:APX-complete 445: 421: 412: 408: 404: 399: 395: 389: 371: 369: 358: 352: 253: 71: 41: 37: 25: 22:graph theory 18:mathematical 15: 1310:: 347–352, 1291:Pósa, Lajos 1287:Erdős, Paul 1233:Dinur, Irit 1050:: 219–234, 770:. See also 757:Karp (1972) 463:L-reduction 365:NP-complete 354:Karp (1972) 349:NP-hardness 46:NP-complete 28:(FVS) of a 1575:Categories 1279:2010-03-29 999:References 372:undirected 254:The graph 248:cycle-free 68:Definition 1342:CiteSeerX 1324:123981328 1131:1004.1672 1100:CiteSeerX 1057:1106.0225 989:198996919 855:0178-4617 539:− 271:∖ 191:≤ 155:⊆ 1529:(1979), 1293:(1965), 1082:10243677 639:problem. 621:deadlock 359:directed 72:The FVS 1490:0975556 1440:1735603 1266:2178966 1226:1547510 1218:2456546 1188:2454063 1136:Bibcode 1074:1765590 1033:1710236 922:Bibcode 863:2437790 816:8762205 599:is the 16:In the 1561:  1543:  1488:  1438:  1400:436224 1398:  1388:  1364:731997 1362:  1344:  1322:  1264:  1224:  1216:  1186:  1154:  1102:  1080:  1072:  1031:  987:  977:  940:  861:  853:  814:  804:  628:abort. 491:Bounds 424:degree 361:graphs 331:forest 60:, and 44:is an 34:cycles 1515:(PDF) 1457:(PDF) 1396:S2CID 1360:S2CID 1320:S2CID 1298:(PDF) 1273:(PDF) 1240:(PDF) 1222:S2CID 1126:arXiv 1078:S2CID 1052:arXiv 985:S2CID 963:(PDF) 859:S2CID 812:S2CID 659:: GT7 644:Notes 309:from 170:with 82:graph 30:graph 1559:ISBN 1541:ISBN 1386:ISBN 1152:ISBN 975:ISBN 938:ISBN 851:ISSN 802:ISBN 633:VLSI 434:for 62:VLSI 24:, a 1476:doi 1428:doi 1376:doi 1352:doi 1312:doi 1254:doi 1250:162 1206:doi 1176:doi 1144:doi 1110:doi 1062:doi 1021:doi 967:doi 930:doi 843:doi 794:doi 615:In 363:is 345:). 1577:: 1539:, 1525:; 1486:MR 1484:, 1472:72 1470:, 1436:MR 1434:, 1424:19 1422:, 1394:, 1384:, 1358:, 1350:, 1338:52 1336:, 1318:, 1308:17 1306:, 1300:, 1289:; 1262:MR 1260:, 1242:, 1220:, 1214:MR 1212:, 1202:55 1200:, 1184:MR 1182:, 1172:74 1170:, 1150:, 1142:, 1134:, 1108:, 1096:83 1094:, 1076:, 1070:MR 1068:, 1060:, 1048:12 1046:, 1029:MR 1027:, 1017:12 1015:, 983:. 973:. 936:. 928:. 857:. 849:. 839:20 837:. 833:. 810:. 800:. 788:. 749:^ 671:; 438:. 419:. 409:O* 56:, 1478:: 1430:: 1378:: 1354:: 1314:: 1256:: 1208:: 1178:: 1146:: 1138:: 1128:: 1112:: 1064:: 1054:: 1036:. 1023:: 991:. 969:: 946:. 932:: 924:: 902:. 890:. 878:. 865:. 845:: 818:. 796:: 733:. 721:. 709:. 697:. 592:. 567:| 563:C 559:| 555:+ 551:| 547:V 543:| 535:| 531:E 527:| 458:; 413:n 405:O 400:n 396:O 317:G 297:X 277:] 274:X 268:V 265:[ 262:G 250:? 234:G 214:X 194:k 187:| 183:X 179:| 158:V 152:X 141:. 129:k 109:) 106:E 103:, 100:V 97:( 94:= 91:G

Index

mathematical
graph theory
graph
cycles
NP-complete
first problems shown to be NP-complete
operating systems
database systems
VLSI
decision problem
graph
cycle-free
forest
directed acyclic graph
directed graphs
directed graphs
Karp (1972)
directed graphs
NP-complete
maximum degree
maximum degree
NP optimization problem
fixed-parameter tractable
degree
polynomial time
matroid parity problem
linear matroids
APX-complete
vertex cover problem
L-reduction

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