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81.
82.
This paper describes an exact algorithm for the Equitable Coloring Problem, based on the well known DSatur algorithm for the classic Coloring Problem with new pruning rules specifically derived from the equity constraint. Computational experiences show that our algorithm is competitive with those known in literature. 相似文献
83.
Olof Heden 《Discrete Mathematics》2006,306(16):1975-1980
Any full rank perfect 1-error correcting binary code of length n=2k-1 and with a kernel of dimension n-log(n+1)-m, where m is sufficiently large, may be used to construct a full rank perfect 1-error correcting binary code of length 2m-1 and with a kernel of dimension n-log(n+1)-k. Especially we may construct full rank perfect 1-error correcting binary codes of length n=2m-1 and with a kernel of dimension n-log(n+1)-4 for m=6,7,…,10.This result extends known results on the possibilities for the size of a kernel of a full rank perfect code. 相似文献
84.
V.V. Mkrtchyan 《Discrete Mathematics》2006,306(4):456-459
I prove that in a tree in which the distance between any two endpoints is even, there is a maximum proper partial 0-1 coloring such that the edges colored by 0 form a maximum matching. 相似文献
85.
We give new bounds on the star arboricity and the caterpillar arboricity of planar graphs with given girth. One of them answers an open problem of Gyárfás and West: there exist planar graphs with track number 4. We also provide new NP-complete problems. 相似文献
86.
Graph Coloring with Adaptive Evolutionary Algorithms 总被引:4,自引:0,他引:4
This paper presents the results of an experimental investigation on solving graph coloring problems with Evolutionary Algorithms (EAs). After testing different algorithm variants we conclude that the best option is an asexual EA using order-based representation and an adaptation mechanism that periodically changes the fitness function during the evolution. This adaptive EA is general, using no domain specific knowledge, except, of course, from the decoder (fitness function). We compare this adaptive EA to a powerful traditional graph coloring technique DSatur and the Grouping Genetic Algorithm (GGA) on a wide range of problem instances with different size, topology and edge density. The results show that the adaptive EA is superior to the Grouping (GA) and outperforms DSatur on the hardest problem instances. Furthermore, it scales up better with the problem size than the other two algorithms and indicates a linear computational complexity. 相似文献
87.
88.
关于联图K_(2,n)∨P_m的邻点可区别的全染色 总被引:1,自引:0,他引:1
一个全染色被称为邻点可区别的如果它满足对任意两个相邻点所关联的色集合不同.本文给出了联图K2,n∨Pm的邻点可区别的全色数并且证明了它满足邻点可区别的全染色猜想. 相似文献
89.
Giuseppe Confessore Paolo Dell''Olmo Stefano Giordani 《Discrete Applied Mathematics》2002,120(1-3):73-90
We study the problem of finding an acyclic orientation of an undirected graph, such that each (oriented) path is covered by a limited number k of maximal cliques. This is equivalent to finding a k-approximate solution for the interval coloring problem on a graph. We focus our attention on claw-free chordal graphs, and show how to find an orientation of such a graph in linear time, which guarantees that each path is covered by at most two maximal cliques. This extends previous published results on other graph classes where stronger assumptions were made. 相似文献
90.
HoKyu Lee 《Discrete Mathematics》2006,306(5):519-525
MacMahon [Combinatory Analysis, vols. I and II, Cambridge University Press, Cambridge, 1915, 1916 (reprinted, Chelsea, 1960)] introduced a perfect partition of positive integer n, which is a partition such that every positive integer less than or equal to n can be uniquely represented by the sum of its parts. We generalize perfect partition and find a relation with ordered factorizations. 相似文献