Graphclass: (P7,star1,2,3,odd anti-cycle)-free
Inclusions
The map shows the inclusions between the current class and a fixed set of landmark classes. Minimal/maximal is with respect
to the contents of ISGCI. Only references for direct inclusions are given. Where no reference is given, check equivalent classes
or use the Java application. To check relations other than inclusion (e.g. disjointness) use the Java application, as well.
Map
Inclusion map for (\co{P_7},\co{star_{1,2,3}},odd anti-cycle)--free
Speed
Speed
[?] The speed of a class $X$ is the function $n \mapsto |X_n|,ドル where $X_n$ is the set of $n$-vertex labeled graphs in $X$.
Depending on the rate of growths of the speed of the class, ISGCI
distinguishes the following values of the parameter:
Constant
Polynomial
Exponential
Factorial
Superfactorial (2ドル^{o(n^2)}$ )
Superfactorial (2ドル^{\Theta(n^2)}$ )
factorial
at least factorial on
(3K1,C4,C5)-free
[
1785]
V.E. Alekseev
On lower layers of a lattice of hereditary classes of graphs
Diskretn. Anal. Issled. Oper. Ser. 1 4:1 3-12 (1997)
[
1786]
E.R. Scheinerman, J. Zito
On the size of hereditary classes of graphs
J. Combin. Th. B Vol. 61 No.1 16-39 (1994)
[
1787]
J. Balogh, B. Bollobas, D. Weinreich
The speed of hereditary properties of graphs
J. Combin. Th. B Vol. 79 No.2 131-156 (2000)
Parameters
acyclic chromatic number
[?] The acyclic chromatic number of a graph $G$ is the smallest size of a vertex partition $\{V_1,\dots,V_l\}$ such that each $V_i$ is an independent set
and for all $i,j$ that graph $G[V_i\cup V_j]$ does not contain a cycle.
Unbounded
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
bandwidth
[?] The bandwidth of a graph $G$ is the shortest maximum "length" of an edge over all one dimensional layouts of $G$. Formally, bandwidth is defined as $\min_{i \colon V \rightarrow \mathbb{N}\;}\{\max_{\{u,v\}\in E\;} \{|i(u)-i(v)|\}\mid i\text{ is injective}\}$.
Unbounded
Unbounded from acyclic chromatic numberUnbounded from book thicknessUnbounded from branchwidthUnbounded from carvingwidthUnbounded from chromatic numberUnbounded from cutwidthUnbounded from degeneracyUnbounded from maximum cliqueUnbounded from maximum degreeUnbounded from pathwidthUnbounded from treewidthUnbounded on
complete
[by definition]
book thickness
[?] A book embedding of a graph $G$ is an embedding of $G$ on a collection of half-planes (called pages) having the same line
(called spine) as their boundary, such that the vertices all lie on the spine and there are no crossing edges. The book thickness of a graph $G$ is the smallest number of pages over all book embeddings of $G$.
Unbounded
Unbounded from acyclic chromatic numberUnbounded from chromatic numberUnbounded from degeneracyUnbounded from maximum cliqueUnbounded on
complete
[
1778]
F. Bernhart, P.C. Kainen
The book thickness of a graph
J. of Combin. Th. (B) 27 320-331 (1979)
booleanwidth
[?] Consider the following decomposition of a graph $G$ which is defined as a pair $(T,L)$ where $T$ is a binary tree and $L$
is a bijection from $V(G)$ to the leaves of the tree $T$. The function $\text{cut-bool} \colon 2^{V(G)} \rightarrow R$ is
defined as $\text{cut-bool}(A)$ := $\log_2|\{S \subseteq V(G) \backslash A \mid \exists X \subseteq A \colon S = (V(G) \backslash
A) \cap \bigcup_{x \in X} N(x)\}|$. Every edge $e$ in $T$ partitions the vertices $V(G)$ into $\{A_e,\overline{A_e}\}$ according
to the leaves of the two connected components of $T - e$. The booleanwidth of the above decomposition $(T,L)$ is $\max_{e
\in E(T)\;} \{ \text{cut-bool}(A_e)\}$. The booleanwidth of a graph $G$ is the minimum booleanwidth of a decomposition of $G$ as above.
Bounded
Bounded from booleanwidth on the complement
Bounded from cliquewidth
Bounded from rankwidth
branchwidth
[?] A branch decomposition of a graph $G$ is a pair $(T,\chi),ドル where $T$ is a binary tree and $\chi$ is a bijection, mapping
leaves of $T$ to edges of $G$. Any edge $\{u, v\}$ of the tree divides the tree into two components and divides the set of
edges of $G$ into two parts $X, E \backslash X,ドル consisting of edges mapped to the leaves of each component. The width of
the edge $\{u,v\}$ is the number of vertices of $G$ that is incident both with an edge in $X$ and with an edge in $E \backslash
X$. The width of the decomposition $(T,\chi)$ is the maximum width of its edges. The branchwidth of the graph $G$ is the minimum width over all branch-decompositions of $G$.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from treewidth
carvingwidth
[?] Consider a decomposition $(T,\chi)$ of a graph $G$ where $T$ is a binary tree with $|V(G)|$ leaves and $\chi$ is a bijection
mapping the leaves of $T$ to the vertices of $G$. Every edge $e \in E(T)$ of the tree $T$ partitions the vertices of the graph
$G$ into two parts $V_e$ and $V \backslash V_e$ according to the leaves of the two connected components in $T - e$. The width
of an edge $e$ of the tree is the number of edges of a graph $G$ that have exactly one endpoint in $V_e$ and another endpoint
in $V \backslash V_e$. The width of the decomposition $(T,\chi)$ is the largest width over all edges of the tree $T$. The
carvingwidth of a graph is the minimum width over all decompositions as above.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from maximum degree
Unbounded from treewidth
chromatic number
[?] The chromatic number of a graph is the minimum number of colours needed to label all its vertices in such a way that no two vertices with the
same color are adjacent.
Unbounded
Unbounded from maximum clique
cliquewidth
[?] The cliquewidth of a graph is the number of different labels that is needed to construct the graph using the following operations:
- creation of a vertex with label $i,ドル
- disjoint union,
- renaming labels $i$ to label $j,ドル and
- connecting all vertices with label $i$ to all vertices with label $j$.
Bounded
Bounded from booleanwidth
Bounded from cliquewidth on the complement
Bounded from rankwidth
cochromatic number
[?] The cochromatic number of a graph $G$ is the minimum number of colours needed to label all its vertices in such a way that that every set of vertices
with the same colour is either independent in G, or independent in $\overline{G}$.
Bounded
cutwidth
[?] The cutwidth of a graph $G$ is the smallest integer $k$ such that the vertices of $G$ can be arranged in a linear layout $v_1,
\ldots, v_n$ in such a way that for every $i = 1, \ldots,n - 1,ドル there are at most $k$ edges with one endpoint in $\{v_1,
\ldots, v_i\}$ and the other in $\{v_{i+1}, \ldots, v_n\}$.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from carvingwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from maximum degree
Unbounded from pathwidth
Unbounded from treewidth
degeneracy
[?] Let $G$ be a graph and consider the following algorithm:
- Find a vertex $v$ with smallest degree.
- Delete vertex $v$ and its incident edges.
- Repeat as long as the graph is not empty.
The degeneracy of a graph $G$ is the maximum degree of a vertex when it is deleted in the above algorithm.
Unbounded
Unbounded from chromatic number
Unbounded from maximum clique
diameter
[?] The diameter of a graph $G$ is the length of the longest shortest path between any two vertices in $G$.
Bounded
Bounded from maximum independent setBounded from maximum induced matchingBounded from minimum clique coverBounded from minimum dominating setBounded on
P7-free
[by definition]
distance to block
[?] The distance to block of a graph $G$ is the size of a smallest vertex subset whose deletion makes $G$ a block graph.
Unbounded
distance to clique
[?] Let $G$ be a graph. Its distance to clique is the minimum number of vertices that have to be deleted from $G$ in order to obtain a clique.
Unbounded
Unbounded from distance to block
Unbounded from distance to cluster
Unbounded from distance to co-cluster
Unbounded from distance to cograph
distance to cluster
[?] A cluster is a disjoint union of cliques. The distance to cluster of a graph $G$ is the size of a smallest vertex subset whose deletion makes $G$ a cluster graph.
Unbounded
Unbounded from distance to block
Unbounded from distance to co-cluster on the complement
Unbounded from distance to cograph
distance to co-cluster
[?] The distance to co-cluster of a graph is the minimum number of vertices that have to be deleted to obtain a co-cluster graph.
Unbounded
Unbounded from distance to cluster on the complement
Unbounded from distance to cograph
distance to cograph
[?] The distance to cograph of a graph $G$ is the minimum number of vertices that have to be deleted from $G$ in order to obtain a cograph .
Unbounded
Unbounded from distance to cograph on the complement
distance to linear forest
[?] The distance to linear forest of a graph $G = (V, E)$ is the size of a smallest subset $S$ of vertices, such that $G[V \backslash S]$ is a disjoint union
of paths and singleton vertices.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from distance to block
Unbounded from distance to outerplanar
Unbounded from maximum clique
Unbounded from pathwidth
Unbounded from treewidth
distance to outerplanar
[?] The distance to outerplanar of a graph $G = (V,E)$ is the minumum size of a vertex subset $X \subseteq V,ドル such that $G[V \backslash X]$ is a outerplanar graph.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from treewidth
genus
[?] The genus $g$ of a graph $G$ is the minimum number of handles over all surfaces on which $G$ can be embedded without edge
crossings.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
max-leaf number
[?] The max-leaf number of a graph $G$ is the maximum number of leaves in a spanning tree of $G$.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from bandwidth
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from carvingwidth
Unbounded from chromatic number
Unbounded from cutwidth
Unbounded from degeneracy
Unbounded from distance to block
Unbounded from distance to linear forest
Unbounded from distance to outerplanar
Unbounded from maximum clique
Unbounded from maximum degree
Unbounded from pathwidth
Unbounded from treewidth
maximum clique
[?] The parameter maximum clique of a graph $G$ is the largest number of vertices in a complete subgraph of $G$.
Unbounded
maximum degree
[?] The maximum degree of a graph $G$ is the largest number of neighbors of a vertex in $G$.
Unbounded
Unbounded from acyclic chromatic numberUnbounded from chromatic numberUnbounded from degeneracyUnbounded from maximum cliqueUnbounded on
complete
[by definition]
maximum independent set
[?] An independent set of a graph $G$ is a subset of pairwise non-adjacent vertices. The parameter maximum independent set of graph $G$ is the size of a largest independent set in $G$.
Bounded
Bounded from maximum clique on the complementBounded from minimum clique coverBounded on
3K1-free
[by definition]
Bounded on
4K1-free
[by definition]
Bounded on
5K1-free
[by definition]
maximum induced matching
[?] For a graph $G = (V,E)$ an induced matching is an edge subset $M \subseteq E$ that satisfies the following two conditions:
$M$ is a matching of the graph $G$ and there is no edge in $E \backslash M$ connecting any two vertices belonging to edges
of the matching $M$. The parameter maximum induced matching of a graph $G$ is the largest size of an induced matching in $G$.
Bounded
Bounded from maximum independent set
Bounded from minimum clique cover
maximum matching
[?] A matching in a graph is a subset of pairwise disjoint edges (any two edges that do not share an endpoint). The parameter
maximum matching of a graph $G$ is the largest size of a matching in $G$.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from distance to block
Unbounded from distance to cluster
Unbounded from distance to co-cluster
Unbounded from distance to cograph
Unbounded from distance to linear forest
Unbounded from distance to outerplanar
Unbounded from maximum clique
Unbounded from pathwidth
Unbounded from tree depth
Unbounded from treewidth
Unbounded from vertex cover
minimum clique cover
[?] A clique cover of a graph $G = (V, E)$ is a partition $P$ of $V$ such that each part in $P$ induces a clique in $G$. The minimum clique cover of $G$ is the minimum number of parts in a clique cover of $G$. Note that the clique cover number of a graph is exactly the
chromatic number of its complement.
Bounded
Bounded from chromatic number on the complement
minimum dominating set
[?] A dominating set of a graph $G$ is a subset $D$ of its vertices, such that every vertex not in $D$ is adjacent to at least
one member of $D$. The parameter minimum dominating set for graph $G$ is the minimum number of vertices in a dominating set for $G$.
Bounded
Bounded from maximum independent set
Bounded from minimum clique cover
pathwidth
[?] A path decomposition of a graph $G$ is a pair $(P,X)$ where $P$ is a path with vertex set $\{1, \ldots, q\},ドル and $X = \{X_1,X_2,
\ldots ,X_q\}$ is a family of vertex subsets of $V(G)$ such that:
- $\bigcup_{p \in \{1,\ldots ,q\}} X_p = V(G)$
- $\forall\{u,v\} \in E(G) \exists p \colon u, v \in X_p$
- $\forall v \in V(G)$ the set of vertices $\{p \mid v \in X_p\}$ is a connected subpath of $P$.
The width of a path decomposition $(P,X)$ is max$\{|X_p| - 1 \mid p \in \{1,\ldots ,q\}\}$. The pathwidth of a graph $G$ is the minimum width among all possible path decompositions of $G$.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from treewidth
rankwidth
[?] Let $M$ be the $|V| \times |V|$ adjacency matrix of a graph $G$. The cut rank of a set $A \subseteq V(G)$ is the rank of the
submatrix of $M$ induced by the rows of $A$ and the columns of $V(G) \backslash A$. A rank decomposition of a graph $G$ is
a pair $(T,L)$ where $T$ is a binary tree and $L$ is a bijection from $V(G)$ to the leaves of the tree $T$. Any edge $e$ in
the tree $T$ splits $V(G)$ into two parts $A_e, B_e$ corresponding to the leaves of the two connected components of $T - e$.
The width of an edge $e \in E(T)$ is the cutrank of $A_e$. The width of the rank-decomposition $(T,L)$ is the maximum width
of an edge in $T$. The rankwidth of the graph $G$ is the minimum width of a rank-decomposition of $G$.
Bounded
Bounded from booleanwidth
Bounded from cliquewidth
Bounded from rankwidth on the complement
tree depth
[?] A tree depth decomposition of a graph $G = (V,E)$ is a rooted tree $T$ with the same vertices $V,ドル such that, for every edge
$\{u,v\} \in E,ドル either $u$ is an ancestor of $v$ or $v$ is an ancestor of $u$ in the tree $T$. The depth of $T$ is the maximum
number of vertices on a path from the root to any leaf. The tree depth of a graph $G$ is the minimum depth among all tree depth decompositions.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from maximum clique
Unbounded from pathwidth
Unbounded from treewidth
treewidth
[?] A tree decomposition of a graph $G$ is a pair $(T, X),ドル where $T = (I, F)$ is a tree, and $X = \{X_i \mid i \in I\}$ is a
family of subsets of $V(G)$ such that
- the union of all $X_i,ドル $i \in I$ equals $V,ドル
- for all edges $\{v,w\} \in E,ドル there exists $i \in I,ドル such that $v, w \in X_i,ドル and
- for all $v \in V$ the set of nodes $\{i \in I \mid v \in X_i\}$ forms a subtree of $T$.
The width of the tree decomposition is $\max |X_i| - 1$.
The treewidth of a graph is the minimum width over all possible tree decompositions of the graph.
Unbounded
Unbounded from acyclic chromatic numberUnbounded from book thicknessUnbounded from branchwidthUnbounded from chromatic numberUnbounded from degeneracyUnbounded from maximum cliqueUnbounded on
complete
[by definition]
vertex cover
[?] Let $G$ be a graph. Its vertex cover number is the minimum number of vertices that have to be deleted in order to obtain an independent set.
Unbounded
Unbounded from acyclic chromatic number
Unbounded from book thickness
Unbounded from branchwidth
Unbounded from chromatic number
Unbounded from degeneracy
Unbounded from distance to block
Unbounded from distance to cluster
Unbounded from distance to co-cluster
Unbounded from distance to cograph
Unbounded from distance to linear forest
Unbounded from distance to outerplanar
Unbounded from maximum clique
Unbounded from maximum matching
Unbounded from pathwidth
Unbounded from tree depth
Unbounded from treewidth
Problems
Problems in italics have no summary page and are only listed when
ISGCI contains a result for the current class.
Parameter decomposition
book thickness decomposition
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff the book thickness of G is at most k.
Unknown to ISGCI
booleanwidth decomposition
[?]
Input:
A graph G in this class.
Output:
An expression that constructs G according to the rules for booleanwidth, using only a constant number of labels.
Undefined if this class has unbounded booleanwidth.
Polynomial
Polynomial from Bounded booleanwidth
cliquewidth decomposition
[?]
Input:
A graph G in this class.
Output:
An expression that constructs G according to the rules for cliquewidth, using only a constant number of labels.
Undefined if this class has unbounded cliquewidth.
Polynomial
Polynomial from Bounded cliquewidth
Polynomial from cliquewidth decomposition on the complement
cutwidth decomposition
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff the cutwidth of G is at most k.
Unknown to ISGCI
treewidth decomposition
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff the treewidth of G is at most k.
Unknown to ISGCI
Unweighted problems
3-Colourability
[?]
Input:
A graph G in this class.
Output:
True iff each vertex of G can be assigned one colour out of 3 such that whenever two vertices are adjacent, they have different colours.
Linear
Linear from FPT-Linear on maximum independent set and Linear decomposition timePolynomial from ColourabilityPolynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on minimum clique cover and Linear decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from FPT-Linear on cliquewidth and Polynomial decomposition timePolynomial on
2P3-free
[
1431]
H. Broersma, P.A. Golovach, D. Paulusma, J. Song
Determining the chromatic number of triangle-free 2P3-free graphs in polynomial time
Manuscript (2010)
Polynomial on
4K1-free
[
1431]
H. Broersma, P.A. Golovach, D. Paulusma, J. Song
Determining the chromatic number of triangle-free 2P3-free graphs in polynomial time
Manuscript (2010)
Polynomial [$O(V^4)$]
on
AT-free
[
1439]
J. Stacho
3-colouring of AT-free graphs in polynomial time
21st International Symposium on Algorithms and Computation ISAAC, Lecture Notes in Comp. Sci. LNCS 6507 144-155 (2010)
Polynomial on
P2 ∪ P4-free
[
1431]
H. Broersma, P.A. Golovach, D. Paulusma, J. Song
Determining the chromatic number of triangle-free 2P3-free graphs in polynomial time
Manuscript (2010)
Polynomial on
P5-free
[
1242]
B. Randerath, I. Schiermeyer, M. Tewes
Three-colourability and forbidden subgraphs II: polynomial algorithms
Discrete Math. 251 137-212 (2002)
[
1441]
C.T. Hoang, M. Kaminski, V. Lozin, J. Sawada, X. Shu
Deciding k-colorability of P_5-free graphs in polynomial time
Algorithmica Vol.57 No.1 74-81 (2010)
Polynomial on
P6-free
[
1243]
B. Randerath, I. Schiermeyer
3-colorability in P for P_6-free graphs
Discrete Appl. Math. 136 299-313 (2004)
Polynomial on
(X91,claw)-free
[
1663]
M. Kaminski, V. Lozin
Vertex 3-colorability of claw-free graphs
Algorithmic Operations Research Vol.2 15-21 (2007)
Polynomial on
co-gem-free
[
1431]
H. Broersma, P.A. Golovach, D. Paulusma, J. Song
Determining the chromatic number of triangle-free 2P3-free graphs in polynomial time
Manuscript (2010)
Polynomial on
nP3-free, fixed n
[
1431]
H. Broersma, P.A. Golovach, D. Paulusma, J. Song
Determining the chromatic number of triangle-free 2P3-free graphs in polynomial time
Manuscript (2010)
Polynomial on
odd-hole-free
[
1744]
(no preview available)
Clique
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff G contains a set S of pairwise adjacent vertices, with |S| >= k.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on cliquewidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from Independent set on the complementPolynomial from Weighted cliquePolynomial on
circular perfect
[
1408]
A. Pecher, A.K. Wagler
Clique and chromatic number of circular-perfect graphs
Proceedings of ISCO 2010 - International Symposium on Combinatorial Optimization, Elec. Notes in Discrete Math 36 199-206
(2010)
Polynomial [$O(V^{2.5}/\log V)$]
on
generalized split
Clique cover
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff the vertices of G can be partitioned into k sets Si, such that whenever two vertices are in the same set Si, they are adjacent.
Polynomial
Polynomial from Colourability on the complementPolynomial from XP on booleanwidth and Polynomial decomposition timePolynomial from XP on cliquewidth and Polynomial decomposition timePolynomial from XP on rankwidth and Linear decomposition timePolynomial [$O(V+E)$]
on
generalized split
[
1798]
E.M. Eschen, X. Wang
Algorithms for unipolar and generalized split graphs
Discrete Applied Math. 162 195-201 (2014)
Colourability
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff each vertex of G can be assigned one colour out of k such that whenever two vertices are adjacent, they have different colours.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on cliquewidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial on
circular perfect
[
1408]
A. Pecher, A.K. Wagler
Clique and chromatic number of circular-perfect graphs
Proceedings of ISCO 2010 - International Symposium on Combinatorial Optimization, Elec. Notes in Discrete Math 36 199-206
(2010)
Polynomial [$O(V^3)$]
on
co-comparability
[
451]
M.C. Golumbic
The complexity of comparability graph recognition and coloring
Computing 18 1977 199--208
Polynomial on
co-paw-free
[
1433]
D. Kral, J. Kratochvil, Z. Tuza, G.J. Woeginger
Complexity of coloring graphs without forbidden induced subgraphs
Proceedings of the 27th International Workshop on Graph-Theoretic Concepts in Computer Science WG'01, LNCS 2204, 254-262 (2001)
Polynomial [$O(V^{2.5}/\log V)$]
on
generalized split
Polynomial on
perfect
[
476]
M. Gr\"otschel, L. Lov\'asz, A. Schrijver
The ellipsoid method and its consequences in combinatorial optimization
Combinatorica 1 169--197, 1981 Corrigendum
Domination
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff G contains a set S of vertices, with |S| <= k, such that every vertex in G is either in S or adjacent to a vertex in S.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from FPT-Linear on cliquewidth and Polynomial decomposition timePolynomial from XP on maximum independent set and Linear decomposition timePolynomial from XP on minimum clique cover and Linear decomposition timePolynomial from XP on minimum dominating set and Linear decomposition timePolynomial on
AT-free
[
1152]
D. Kratsch
Domination and total domination in asteroidal triple-free graphs
Discrete Appl. Math. 99 No.1-3, 111-123 (2000)
Polynomial [$O(VE)$]
on
(claw,net)-free
[
1127]
A. Brandstaedt, F. Dragan
On linear and circular structure of (claw, net)-free graph
To appear in Discrete Appl. Math.
Polynomial on
co-comparability
[
1150]
D. Kratsch, L. Stewart
Domination on cocomparability graphs
SIAM J. Discrete Math. 6(3) (1993) 400-417
[
1151]
H. Breu, D.G. Kirkpatrick
Algorithms for the dominating set and Steiner set problems in cocomparability graphs
Manuscript 1993
Feedback vertex set
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff G contains a set S of vertices, with |S| <= k, such that every cycle in G contains a vertex from S.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on cliquewidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from Weighted feedback vertex setPolynomial from XP on maximum independent set and Linear decomposition timePolynomial from XP on minimum clique cover and Linear decomposition timePolynomial [$O(V^8E^2)$]
on
AT-free
[
1581]
Feedback vertex set on AT-free graphs
D. Kratsch, H. Mueller, I. Todinca
Discrete Appl. Math. 156 No. 10 1936-1947 (2008)
Polynomial [$O(V^2E)$]
on
co-comparability
[
1579]
M.S Chang, Y.D. Liang
Minimum feedback vertex set in cocomparability graphs and convex bipartite graphs
Acta Informatica 34 337-346 (1997)
Polynomial [$O(V^4)$]
on
co-comparability
[
1578]
S.R. Coorg, C.P. Rangan
Feedback vertex set on cocomparability graphs
Networks 26 101-111 (1995)
Graph isomorphism
[?]
Input:
Graphs G and H in this class
Output:
True iff G and H are isomorphic.
Polynomial
Polynomial from Graph isomorphism on the complement
Polynomial from XP on booleanwidth and Polynomial decomposition time
Polynomial from XP on cliquewidth and Polynomial decomposition time
Polynomial from XP on rankwidth and Linear decomposition time
Hamiltonian cycle
[?]
Input:
A graph G in this class.
Output:
True iff G has a simple cycle that goes through every vertex of the graph.
Linear
Polynomial from FPT on maximum independent set and Linear decomposition timePolynomial from FPT on minimum clique cover and Linear decomposition timePolynomial from XP on booleanwidth and Polynomial decomposition timePolynomial from XP on cliquewidth and Polynomial decomposition timePolynomial from XP on rankwidth and Linear decomposition timeLinear on
(P6,claw)-free
[
1694]
(no preview available)
Linear on
(claw,net)-free
[
1610]
A. Brandstaedt, F.F. Dragan, E. Koehler
Linear time algorithms for the Hamiltonian problems on (claw,net)-free graphs
SIAM J. Computing 30 1662-1677 (2000)
Polynomial on
3K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
4K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
5K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
(claw,net)-free
[
344]
D. Duffus, R.J. Gould, M.S. Jacobson
Forbidden subgraphs and the Hamiltonian theme.
The theory and applications of graphs, 4th int. Conf., Kalamazoo/Mich. 1980, 297-316 (1981).
Polynomial on
co-comparability
[
1524]
J.S. Deogun, G. Steiner
Polynomial Algorithms for Hamiltonian Cycle in Cocomparability Graphs
SIAM J. Computing 23 Issue 3 520-552 (1994)
Hamiltonian path
[?]
Input:
A graph G in this class.
Output:
True iff G has a simple path that goes through every vertex of the graph.
Linear
Polynomial from FPT on maximum independent set and Linear decomposition timePolynomial from FPT on minimum clique cover and Linear decomposition timePolynomial from XP on booleanwidth and Polynomial decomposition timePolynomial from XP on cliquewidth and Polynomial decomposition timePolynomial from XP on rankwidth and Linear decomposition timeLinear on
(claw,net)-free
[
1610]
A. Brandstaedt, F.F. Dragan, E. Koehler
Linear time algorithms for the Hamiltonian problems on (claw,net)-free graphs
SIAM J. Computing 30 1662-1677 (2000)
Polynomial on
3K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
4K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
5K1-free
[
1861]
N. Jedličková, J. Kratochvil
On the structure of Hamiltonian graphs with small independence number
Combinatorial Algorithms. IWOCA 2024. LNCS 14764 180-192 (2024)
Polynomial on
(claw,net)-free
[
344]
D. Duffus, R.J. Gould, M.S. Jacobson
Forbidden subgraphs and the Hamiltonian theme.
The theory and applications of graphs, 4th int. Conf., Kalamazoo/Mich. 1980, 297-316 (1981).
Polynomial on
co-comparability
[
1524]
J.S. Deogun, G. Steiner
Polynomial Algorithms for Hamiltonian Cycle in Cocomparability Graphs
SIAM J. Computing 23 Issue 3 520-552 (1994)
Independent dominating set
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff G contains a set S of pairwise non-adjacent vertices, with |S| <= k, such that every vertex in G is either in S or adjacent to a vertex in S.
Polynomial
Polynomial from Weighted independent dominating set
Independent set
[?]
Input:
A graph G in this class and an integer k.
Output:
True iff G contains a set S of pairwise non-adjacent vertices, such that |S| >= k.
Linear
Linear from Weighted independent setPolynomial from Clique on the complementPolynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on cliquewidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from Weighted independent setPolynomial from XP on maximum independent set and Linear decomposition timePolynomial from XP on minimum clique cover and Linear decomposition timeLinear on
co-comparability
[
1100]
R.M. McConnell, J.P. Spinrad
Modular decomposition and transitive orientation
Discrete Math. 201 (1999) 189-241
Polynomial on
(C6,K3,3+e,P,P7,X37,X41)-free
[
1346]
N.V.R. Mahadev, B.A. Reed
A note on vertex orders for stability number
J. Graph Theory 30 113-120 (1999)
Polynomial on
(E,P)-free
[
1305]
M.U. Gerber, V.V. Lozin
Robust algorithms for the stable set problem
Graphs and Combin., to appear
Polynomial on
(K2,3,P,P5)-free
[
1107]
N.V.R. Mahadev
Vertex deletion and stability number
Research report ORWP 90/2 Dept. of Mathematics, Swiss Fed.Inst. of Technology 1990
[
1346]
N.V.R. Mahadev, B.A. Reed
A note on vertex orders for stability number
J. Graph Theory 30 113-120 (1999)
Polynomial [$O(nm)$]
on
(K3,3-e,P5,X98)-free
[
1117]
A. Brandstaedt, V.V. Lozin
A note on \alpha-redundant vertices in graphs.
Discrete Appl. Math. 108 (2001) 301-308
Polynomial [$O(V^{5})$]
on
(K3,3-e,P5,X99)-free
[
1307]
M.U. Gerber, A. Hertz, D. Schindl
P_5-free graphs and the maximum stable set problem
Discrete Appl. Math. 132 109-119 (2004)
Polynomial on
(K3,3-e,P5)-free
[
1246]
V. Alekseev, P. Lozin, R. Mosca
Maximum independent set problem and P_5-free graphs
Manuscript 2004
Polynomial [$O(VE)$]
on
(P,P5)-free
[
1117]
A. Brandstaedt, V.V. Lozin
A note on \alpha-redundant vertices in graphs.
Discrete Appl. Math. 108 (2001) 301-308
Polynomial [$O(V^8)$]
on
(P,P7)-free
[
1351]
V.E. Alekseev, V.V. Lozin
Augmenting graphs for independent sets
Discrete Appl. Math. 145, No.1 3-10 (2004)
Polynomial on
(P,P8)-free
[
1306]
M.U. Gerber, A. Hertz, V.V. Lozin
Stable sets in two subclasses of banner-free graphs
Discrete Appl. Math. 132 121-136 (2004)
Polynomial on
(P,T2)-free
[
1305]
M.U. Gerber, V.V. Lozin
Robust algorithms for the stable set problem
Graphs and Combin., to appear
Polynomial on
(P,star1,2,5)-free
[
1349]
V.L. Lozin, M. Milanic
On finding augmenting graphs
Rutcor Research Report 28-2005
Polynomial [$O(VE)$]
on
(claw,net)-free
[
1127]
A. Brandstaedt, F. Dragan
On linear and circular structure of (claw, net)-free graph
To appear in Discrete Appl. Math.
[
515]
P.L. Hammer, N.V.R. Mahadev, D. de Werra
The struction of a graph: application to CN--free graphs
Combinatorica 5 1985 141--147
Polynomial on
claw-free
[
947]
N. Sbihi
Algorithme de recherche d'un stable de cardinalit\'e maximum dans un graphe sans \'etoile
Discrete Math. 29 1980 53--76
Polynomial on
co-hereditary clique-Helly
[
1298]
E. Prisner
Hereditary clique-helly graphs
J. Comb. Math. Comb. Comput 14 216-220 (1993)
Polynomial [$O(V+E)$]
on
generalized split
[
1798]
E.M. Eschen, X. Wang
Algorithms for unipolar and generalized split graphs
Discrete Applied Math. 162 195-201 (2014)
Maximum cut
[?] (decision variant)
Input:
A graph G in this class and an integer k.
Output:
True iff the vertices of G can be partitioned into two sets A,B such that there are at least k edges in G with one endpoint in A and the other endpoint in B.
Polynomial
Polynomial from XP,W-hard on booleanwidth and Polynomial decomposition time
Polynomial from XP,W-hard on cliquewidth and Polynomial decomposition time
Polynomial from XP,W-hard on rankwidth and Linear decomposition time
Monopolarity
[?]
Input:
A graph G in this class.
Output:
True iff G is monopolar.
Polynomial
Polarity
[?]
Input:
A graph G in this class.
Output:
True iff G is polar.
Linear
Recognition
[?]
Input:
A graph G.
Output:
True iff G is in this graph class.
Polynomial
Polynomial from Recognition on the complement
Weighted problems
Weighted clique
[?]
Input:
A graph G in this class with weight function on the vertices and a real k.
Output:
True iff G contains a set S of pairwise adjacent vertices, such that the sum of the weights of the vertices in S is at least k.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on cliquewidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from Weighted independent set on the complementPolynomial on
bipartite ∪ co-bipartite ∪ split
Polynomial on
co-comparability ∪ comparability
Polynomial on
interval filament
[
1159]
F. Gavril
Maximum weight independent sets and cliques in intersection graphs of filaments.
Information Processing Letters 73(5-6) 181-188 (2000)
Weighted feedback vertex set
[?]
Input:
A graph G in this class with weight function on the vertices and a real k.
Output:
True iff G contains a set S of vertices, such that the sum of the weights of the vertices in S is at most k and every cycle in G contains a vertex from S.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition time
Polynomial from FPT on rankwidth and Linear decomposition time
Polynomial from FPT-Linear on cliquewidth and Polynomial decomposition time
Polynomial from XP on maximum independent set and Linear decomposition time
Polynomial from XP on maximum induced matching and Linear decomposition time
Polynomial from XP on minimum clique cover and Linear decomposition time
Weighted independent dominating set
[?]
Input:
A graph G in this class with weight function on the vertices and a real k.
Output:
True iff G contains a set S of pairwise non-adjacent vertices, with the sum of the weights of the vertices in S at most k, such that every vertex in G is either in S or adjacent to a vertex in S.
Polynomial
Polynomial from FPT on booleanwidth and Polynomial decomposition time
Polynomial from FPT on rankwidth and Linear decomposition time
Polynomial from FPT-Linear on cliquewidth and Polynomial decomposition time
Polynomial from XP on maximum independent set and Linear decomposition time
Polynomial from XP on minimum clique cover and Linear decomposition time
Weighted independent set
[?]
Input:
A graph G in this class with weight function on the vertices and a real k.
Output:
True iff G contains a set S of pairwise non-adjacent vertices, such that the sum of the weights of the vertices in S is at least k.
Linear
Polynomial from FPT on booleanwidth and Polynomial decomposition timePolynomial from FPT on rankwidth and Linear decomposition timePolynomial from FPT-Linear on cliquewidth and Polynomial decomposition timePolynomial from Weighted clique on the complementPolynomial from XP on maximum independent set and Linear decomposition timePolynomial from XP on minimum clique cover and Linear decomposition timeLinear on
AT-free ∩ claw-free
[
1157]
H. Hempel, D. Kratsch
On claw-free asteroidal triple-free graphs
Discrete Appl. Math. 121, No.1-3, 155-180 (2002)
Polynomial on
3K1-free
[trivial]
Polynomial on
4K1-free
[trivial]
Polynomial on
5K1-free
[trivial]
Polynomial [$O(V^4)$]
on
AT-free
[
160]
H. Broersma, T. Kloks, D. Kratsch, H. M\"uller
Independent sets in asteroidal triple-free graphs
SIAM J. Discrete Math. 12, No.2, 276-287 (1999)
Polynomial [$O(V^5E^3)$]
on
Berge ∩ bull-free
[
1278]
C.M.H. de Figueiredo, F. Maffray
Optimizing bull-free perfect graphs
SIAM J. Discrete Math. Vol.18 No.2 226-240 (2004)
Polynomial on
(K1,4,P,P5,fork)-free
[
1103]
A. Brandstaedt, P.L Hammer
On the stability number of claw-free, P_5-free and more general graphs.
Rutcor Research Report 27-97 1997
Polynomial [$O(n^5)$]
on
(K1,4,P5)-free
[
1110]
R. Mosca
Polynomial algorithms for the maximum stable set problem on particular classes of P_5-free graphs
Information Processing Letters 61 (1997) 137-144
Polynomial on
K2 ∪ claw-free
[
1290]
V. Lozin, R. Mosca
Independent sets and extensions of 2K_2-free graphs
Discrete Appl. Math. 146 74-80 (2005)
Polynomial on
(K2,3,P,P5)-free
[
1107]
N.V.R. Mahadev
Vertex deletion and stability number
Research report ORWP 90/2 Dept. of Mathematics, Swiss Fed.Inst. of Technology 1990
Polynomial on
(K2,3,P,hole)-free
[
1107]
N.V.R. Mahadev
Vertex deletion and stability number
Research report ORWP 90/2 Dept. of Mathematics, Swiss Fed.Inst. of Technology 1990
Polynomial on
(K2,3,P5)-free
[
1110]
R. Mosca
Polynomial algorithms for the maximum stable set problem on particular classes of P_5-free graphs
Information Processing Letters 61 (1997) 137-144
Polynomial [$O(n^6)$]
on
(K3,3,P5)-free
Polynomial [$O(n^8)$]
on
(K4,4,P5)-free
Polynomial on
(P,P5)-free
[
1353]
A. Brandstaedt, C.T. Hoang
On clique separators, nearly chordal graphs, and the Maximum Weight Stable Set Problem
Theoretical Comp. Sci. 389, No.1-2, 295-306 (2007)
Polynomial [$O(V^9 E)$]
on
(P,P7)-free
[
1452]
R. Mosca
Stable sets of maximum weight in (P_7, banner)-free graphs
Discrete Math. 308 Issue 1 20-33 (2008)
Polynomial on
(P5,X82,X83)-free
[
1246]
V. Alekseev, P. Lozin, R. Mosca
Maximum independent set problem and P_5-free graphs
Manuscript 2004
Polynomial [$O(n^4)$]
on
(P5,claw)-free
[
1110]
R. Mosca
Polynomial algorithms for the maximum stable set problem on particular classes of P_5-free graphs
Information Processing Letters 61 (1997) 137-144
Polynomial on
(P5,cricket)-free
[
1110]
R. Mosca
Polynomial algorithms for the maximum stable set problem on particular classes of P_5-free graphs
Information Processing Letters 61 (1997) 137-144
Polynomial [$O(VE)$]
on
(P5,fork)-free
[
1125]
A. Brandstaedt, V.B. Le, H.N. de Ridder
Efficient robust algorithms for the maximum weight stable set problem in chair-free graph classes.
Universitaet Rostock, Fachbereich Informatik, Preprint CS-14-01
Polynomial on
P5-free
[
1635]
D. Lokshantov, M. Vatshelle, Y. Villanger
Independent set in P5-free graphs in polynomial time
Accepted for publication
Polynomial on
P6-free
[
1839]
A. Grzesik, T. Klimosova, M. Pilipczuk
Polynomial-time Algorithm for Maximum Weight Independent Set on P6-free Graphs
ACM Transactions on Algorithms 18 No.1 1-57 (2022)
Polynomial [$O(VE)$]
on
(bull,fork)-free
[
1124]
A. Brandstaedt, C.T. Hoang, V.B. Le
Stability number of bull- and chair-free graphs revisited
to appear in Discrete Appl. Math.
[
307]
C. De Simone, A. Sassano
Stability number of bull-- and chair--free graphs
Discrete Appl. Math. 41 1993 121--129
Polynomial on
claw-free
[
783]
G.J. Minty
On maximal independent sets of vertices in claw--free graphs
J. Comb. Theory (B) 28 1980 284--304
Polynomial [$O(VE)$]
on
co-gem-free
Polynomial on
fork-free
[
1099]
V.E. Alekseev
A polynomial algorithm for finding maximum independent sets in fork-free graphs
Discrete Ann. Operation Res., Ser. 1 6 (1999) 3-19 (in Russian)
Polynomial on
interval filament
[
1159]
F. Gavril
Maximum weight independent sets and cliques in intersection graphs of filaments.
Information Processing Letters 73(5-6) 181-188 (2000)
Polynomial on
(n+4)-pan-free
[
1447]
A. Brandstaedt, V.V. Lozin, R. Mosca
Independent sets of maximum weight in apple-free graphs
SIAM J. Discrete Math. Vol.24 No.1 239-254 (2010)
Polynomial [$O(n^{6p+2})$]
on
(p,q<=2)-colorable
[
1116]
V.E. Alekseev, V.V. Lozin
Independent sets of maximum weight in (p,q)-colorable graphs
Rutcor Research Report 12-2002
Polynomial on
perfect
[
476]
M. Gr\"otschel, L. Lov\'asz, A. Schrijver
The ellipsoid method and its consequences in combinatorial optimization
Combinatorica 1 169--197, 1981 Corrigendum
Polynomial on
subtree overlap
[
1123]
E. Cenek, L. Stewart
Maximum independent set and maximum clique algorithms for overlap graphs
Discrete Appl. Math. 131, No.1 77-91 (2003)
Weighted maximum cut
[?]
(decision variant)
Input:
A graph G in this class with weight function on the edges and a real k.
Output:
True iff the vertices of G can be partitioned into two sets A,B such that the sum of weights of the edges in G with one endpoint in A and the other endpoint in B is at least k.
NP-complete
NP-complete on
2K1-free
[
1676]
M. Kaminski
Max-cut and containment relations in graphs
Proceedings of WG 2010, Lecture Notes in Computer Science 6410, 15-26 (2010)