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Information Processing Letters 78 (2001) 5–336 Subject Index to Volumes 1–75 The numbers mentioned in this Subject Index refer to the Reference List of Indexed Articles (pp. 337–448 of this issue). 0, 1 semaphore, 470 1NPDA, 894 0, 1 sequence, 768 1T-NPDA, 1065 (0, 1)-CVP, 2395 1T-NPDA(1), 1065 (0, 1)-matrix, 2395, 2462, 2588, 3550 1T-NPDA(k), 1065 (0, 2)-graph, 583 1-approximation algorithm, 3109 0/1 knapsack problem, 2404, 2529 1-bounded conflict free Petri net, 2154, 2369 0L 1-center, 3000 language, 47, 2665 1-colourable, 2299 scheme, 940 1-conservative Petri net, 2253 system, 47, 940 1-copy serializability, 3001 systems, 297 1-dimensional space, 281 0L-D0L equivalence problem, 456 1-DNF consistent with a positive sample, 3856 0-1 1-edge fault tolerant, 3467 integer programming, 3597 1-EFT graph, 3467 law, 3232, 3276 1-EFT(G), 3467 linear programming, 1533 graph, 3467 matrix, see (0, 1)-matrix 1-enabled, 67 polynomial, 436 1-factor, 234 programming, 216 1-fault tolerant design, 3997 resource, 648 for token rings, 3997 0-capacity channel, 2055 1-Hamiltonian, 3997 0-dimensional object, 281 graph, 3675, 3997 0.5-bounded, 2404 1-inkdot Turing machine, 2473, 2752 greedy algorithm, 2404, 2529 1-MFA, 2063 (1, 0)/(1, 1) ms precedence form, 955 1-neighborhood chordal, 3703 (1, 1)-disjoint Boolean sums, 3711 1-persistent protocol, 2487 (1, 1)-method, 26 1-resilient symmetric function, 2677 1ACMP-(k, i), 1139 1-restricted ETOL system, 778 1DFA, 663 1-SDR, 510 1DFA(3), 1371 problem, 510 1DFA(k), 1371 1-sided error logspace polynomial expected time, 1DPDA, 1103 2616 1GDSAFA, 2038 1-spiral polygon, 2939 1NFA, 663, 1065 1-vertex ranking, 3217 1NFA(2), 1065 1-way checking stack automaton language, 144 1NFA(k), 1065 1-width, 3658 0020-0190/2001 Published by Elsevier Science B.V. PII:S0020-0190(01)00175-2 6 Subject Index / Information Processing Letters 78 (2001) 5–336 1-writer multireader Boolean atomic variable, 2138 subgraph problem, 3456 1-writer multireader multivalued atomic 2-colors graph partition, 2597 register, 1721 problem, 2597 variable, 2138 2-competitive 1-writer 2-server algorithm, 2216 multireader multivalued regular variable, 2138 algorithm, 3038 register, 1721 2-connected planar graph, 2010 2×2 algorithm, 351 2-D, see also 2D 2n class of moduli sets, 4107 array grammar, 1244 2n-ary tree, 1126 binary image, 2873, 3089 2ACMP(k, i), 1139 convolution, 2592 2AFA(1) = 1P2NFA(1) = Reg, 2145 grammar, 1244 2AFA(l), 2145 image transposition encryption, 3428 2CNF, 4055 language, 1244 formula, 3829 mesh of processors, 2673 2D, see also 2-D orthogonal wavelet transform, 2592 curved object, 2690 2-D string, 2242 C-string, 3614 matching problem, 2242 linear, 271 representation of a picture, 2242 linearity problem, 271 2-D string, 3614 torus, 2354 wormhole-routed mesh multicomputers, 4038 wavelet transform, 2592 2DFA, 663 2-DA, 395 2DFA(k), 1371 2-dimensional, 1699 2DPDA, 182, 547, 836, 909, 2930 checkboard, 857 with output, 182 convex hull problem, 363 without output, 182 mesh connected computer, 1810 2DPDA(1), 1022 space, 1014 2DPDA(k), 909 2-edge connected 2D-dimensional ECDF searching problem, 1583 graph, 3584 2D-matching spanning subgraph, 3737 algorithm, 2633 2-evader problem, 3261 problem, 2633 2-independent set, 2474 2LG, 1059 problem, 3456 specification, 1059 2-modular tree transformation, 2078 2N − k-closure problem, 3268 2-node connected, 3737 2NFA, 663 2-permutation, 175 2NPDA, 740, 894 2-process consensus, 1808 language, 894 2-processor 2NPDA(k), 814 simulation strategies, 3044 2PFA, 2488 tasks scheduling, 1027 2PP, 2058 2-QBF, 3237 2SAT, 3683 truth, 2597, 3237 2-3 tree, 206, 268, 365, 427, 475, 921, 2762, 3817 2-recipient 2-acyclic family of subtrees, 3703 1-buffer problem, 2192 2-APMPOTA, 571 problem, 2192 2-cache problem, 3558 2-REF, 3242 2-CGP, 2597 2-register machine, 4062 2-chain edge packing, 1842 2-restricted ETOL system, 778 2-CNF, 419, 1540, 2467, 3237 2-SAT formula, 2716 formula, 1540, 2467, 4003 2-satisfiability, 419, 630, 3079 satisfiability, 2597 2-SDR problem, 510 2-CNFSAT, 2597 2-sep chordal graph, 2499 2-colorable, 2299 2-server algorithm, 4066 Subject Index / Information Processing Letters 78 (2001) 5–336 7 2-server problem, 2216, 3558 3-spanner problem, 3347 2-state RCA, 2430 3-square free morphism, 915 2-tabled ETOL system, 778 3-Steiner distance, 3129 2-terminal problem, 1975 3-valued 2-treshold graph, 3073, 3173 shared variable, 3119 2-tree, 3620 wakeup protocol, 3119 2-way 3-way tree, 2718 deterministic pushdown automaton, 2930 4NF, 3533 infinite automaton with a pebble, 2262 relation scheme, 3533 2.5-factor approximation algorithm, 3667 4-canonical decomposition, 3542 2.5-times optimal algorithm, 530 4-colorable graph, 3561 3 symbol alphabet, 3 4-coloring, 353 3/2-approximation algorithm, 4117 4-connected 3D, see also 3-D array, 1244 drawing, 3561 planar graph, 1127, 1926, 3542 straight line grid drawing, 3561 plane triangulation, 1926 3n probe algorithm, 1236 set, 3696 3NF, 798, 2449, 2751, 3533 4-connectivity, 1926 3SAT, 561, 2067 test, 1926 3-approximation algorithm, 4016, 4023 4-star graph, 2583 3-colorable, 1395 5-coloring, 353, 1395 graph, 2534, 3446 5-connectivity, 1926 3-coloring, 2340, 2808 5-pebble automaton, 857 a graph, 1001 (6, 2)-chordal bipartite graph, 2643 of a planar graph, 353 6-competitive, 3315 3-colourable, 3651 6-head deterministic two-way finite automation, 3-colouring, 3651 1371 3-competitive, 4100 6-queens solution, 1767 3-connected, 2058 6-restricted ETOL system, 778 graph, 441, 2058 7-colored, 353 3-connectivity, 1926 7-coloring of planar graphs, 2340 3-D, see also 3D 7-multiplication method, 377 depth information, 3554 8-connectivity, 3127 torus of processors, 2390 8-puzzle problem, 1690 3-dimensional 8-restricted ETOL system, 778 dominance searching problem, 3746 9DLT matrices, 3614 information, 3554 15-puzzle, 2314, 3167 matching, 2088 80-20 rule, 449 ◦ 3-element subset, 478 360 visibility, 3710 3-free D0L language, 948 802.4, 3501 3-layer network, 1762 network, 3501 3-matroid intersection problem, 130 1108 Lisp, 496 3-move identification scheme, 2997 3990 control unit, 1591 3-net wiring, 2508 3-partition, 1044, 1393 A 3-recipient 1-buffer problem, 2192 a posteriori methods, 229 3-regular planar apriori 1-Hamiltonian, 3997 statistic, 49 graph, 2652 weight, 179 Hamiltonian graph, 3675 (a, b)-tree, 1261 3-restricted ETOL system, 778 A/D converter, 3898 3-SAT, 1802, 2731, 3087 A60D, 501 3-SAT = SAT, 3087 An, 13, 330, 1279 ∗ 3-SATISFIABILITY, 561 A , 1690, 1973, 2090, 2382, 2502, 2511 ∗ ∗ 3-space, 746, 1057, 3599 A × b , 2502 8 Subject Index / Information Processing Letters 78 (2001) 5–336 ∗ A -algorithm, 3592 abstract program, 412 Aanderaa-Rosenberg conjecture, 344 fragment, 1941 Aaron, Eric, 3616 abstract Aarts, 3527 programming language, 151 Abadi, 2282 relational algebra, 1881 Abadi, Lamport, and Plotkin, 2817 abstract semantics, 1035, 3920 Abadi, M. et al., 2282 of programs, 2707 Abbasi, Sarmad, 3513 abstract specification, 2282 abduction, 3386 of data structures, 620 Abdulla and Jonsson, 4021 abstract Abd-Alla, 609 structure, 284 Abelian syntax, 544 group, 30, 259, 1129, 2938, 3019 tape, 261 monoid, 3760 type, 412, 945 Ablow, Yoeli, and Turner, 162 Voronoi diagram, 3599 abnegation incident, 1811 abstracting numeric constraints, 4111 abort, 1422 abstraction, 1934, 3418, 3920, 3921 absence of algorithm, 1343 dead values, 1456 in linear space, 1343 deadlock, 962 process, 1343 forwards conflicts, 129 AC, 2252, 3644 live lock, 962 compatible, 3760 useless values, 1456 AC0, 2225, 2847, 3518 absolute reduction, 2349 1-center, 3000 AC0 = NC1, 2847 entropy, 2112 AC0-reducible, 2349 error, 3422, 3993 ACAC0 function, 3939 liveness, 1173 ACC0, 2600 privacy, 957 accelerated integer GCD algorithm, 3443 value, 138, 564, 2377, 3098, 3483, 4088 acceptable abstract identity, 4042 architecture, 3163 in the strong sense, 1550 basis, 1662 acceptance, 59 behavioral characteristics of windows, 1755 in the strong sense, 1550 computation model, 120 abstract data of an array, 71 structure, 105 test, 1713 type, 261, 412, 620, 674, 1399, 1506, 1520, testing, 3022 2263, 3633 acceptation abstract by multitape automata, 752 datatype, 316, 2068 in the weak sense, 1550 design, 3649 of nonregular languages, 1550 domain, 2348 accepted filter, 2679 by a finite automaton, 497 formalism, 172 in deterministic polynomial time, 2112 formulation, 307 string, 2549 for-loop, 443 word, 1550 graph, 1652 accepting and generating rewriting systems, 3074 abstract interpretation, 2348, 2679, 2707, 3920, accepting computation, 814 4111 tree, 1550 framework, 3303 accepting abstract configuration, 666 machine, 1767, 2431, 3163, 3198 DPDA computations, 539 model, 63, 370, 1066, 1130 only regular languages, 2145 operation, 1520 state, 112, 201 production system, 3630 acceptor, 395, 571, 722, 749, 1981, 3139 Subject Index / Information Processing Letters 78 (2001) 5–336 9 acceptor for dependencies, 3360 a language, 1576 system, 3397 an sometric parallel context free array language, activation, 868, 1535 749 of actions, 1535 access control, 237, 1062, 1532, 1688, 1831, 2298 tree, 579 mechanism, 237, 654 active method, 654 attack, 3659 access node, 1512 cost, 224 processes, 1126, 1716 distribution, 1527 actual efficiency, 895 edge, 4071 frequency, 2114, 2373 parameter, 1817 function, 105 termination problem, 501 mechanism movement, 756 ACU compatible, 3760 methods for image databases, 3614 reduction ordering, 3760 modality, 333 acyclic, 2007, 3703 of data, 1855, 2996 c-e structure, 1788 operation, 2950 database schema, 1026 path,
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  • Algorithmic Graph Theory Part III Perfect Graphs and Their Subclasses

    Algorithmic Graph Theory Part III Perfect Graphs and Their Subclasses

    Algorithmic Graph Theory Part III Perfect Graphs and Their Subclasses Martin Milanicˇ [email protected] University of Primorska, Koper, Slovenia Dipartimento di Informatica Universita` degli Studi di Verona, March 2013 1/55 What we’ll do 1 THE BASICS. 2 PERFECT GRAPHS. 3 COGRAPHS. 4 CHORDAL GRAPHS. 5 SPLIT GRAPHS. 6 THRESHOLD GRAPHS. 7 INTERVAL GRAPHS. 2/55 THE BASICS. 2/55 Induced Subgraphs Recall: Definition Given two graphs G = (V , E) and G′ = (V ′, E ′), we say that G is an induced subgraph of G′ if V ⊆ V ′ and E = {uv ∈ E ′ : u, v ∈ V }. Equivalently: G can be obtained from G′ by deleting vertices. Notation: G < G′ 3/55 Hereditary Graph Properties Hereditary graph property (hereditary graph class) = a class of graphs closed under deletion of vertices = a class of graphs closed under taking induced subgraphs Formally: a set of graphs X such that G ∈ X and H < G ⇒ H ∈ X . 4/55 Hereditary Graph Properties Hereditary graph property (Hereditary graph class) = a class of graphs closed under deletion of vertices = a class of graphs closed under taking induced subgraphs Examples: forests complete graphs line graphs bipartite graphs planar graphs graphs of degree at most ∆ triangle-free graphs perfect graphs 5/55 Hereditary Graph Properties Why hereditary graph classes? Vertex deletions are very useful for developing algorithms for various graph optimization problems. Every hereditary graph property can be described in terms of forbidden induced subgraphs. 6/55 Hereditary Graph Properties H-free graph = a graph that does not contain H as an induced subgraph Free(H) = the class of H-free graphs Free(M) := H∈M Free(H) M-free graphT = a graph in Free(M) Proposition X hereditary ⇐⇒ X = Free(M) for some M M = {all (minimal) graphs not in X} The set M is the set of forbidden induced subgraphs for X.
  • Greedy Defining Sets of Graphs

    Greedy Defining Sets of Graphs

    Greedy defining sets of graphs Manouchehr Zaker Department of Mathematical Sciences, Sharif University of Technology, P.O. Box 11365-9415, Tehran, IRAN [email protected] Abstract For a graph G and an order a on V(G), we define a greedy defining set as a subset S of V(G) with an assignment of colors to vertices in S, such that the pre-coloring can be extended to a x( G)-coloring of G by the greedy coloring of (G, a). A greedy defining set ofaX( G)-coloring C of G is a greedy defining set, which results in the coloring C (by the greedy procedure). We denote the size of a greedy defining set of C with minimum cardinality by G D N (G, a, C). In this paper we show that the problem of determining GDN(G,a,C), for an instance (G,a,C) is an NP-complete problem. 1 Introduction and preliminaries We begin with some terminology and notation which are used throughout the paper. For the other necessary definitions and notation, we refer the reader to texts such as [4]. A harmonious coloring of a graph G is a proper vertex coloring of G, such that the subgraph induced on any two different colors has at most one edge. By a hypergraph we mean an ordinary hypergraph which consists of a vertex set V and a collection of subsets of V, called (hyper)edges. In a hypergraph 1£ a block­ ing set is a subset of the vertex set which intersects every edge of 1£.