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Physical Sciences and Mathematics Commons™
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Full-Text Articles in Physical Sciences and Mathematics
A Color-Exchange Algorithm For Exact Graph Coloring, Thomas J. Sager, Shi-Jen Lin
A Color-Exchange Algorithm For Exact Graph Coloring, Thomas J. Sager, Shi-Jen Lin
Computer Science Technical Reports
DEXCH, a color-exchange exact graph coloring algorithm is presented. On many classes of graphs, DEXCH can, in the mean, find the chromatic number of a graph considerably faster than the DSATUR algorithm. The improvement over DSATUR stems from the ability to reorganize the subset of colored vertices and to detect in certain instances the existence of a complete subgraph of cardinality equal to the number of colors used in the best coloring found so far. The mean improvement over DSATUR is greatest on high edge-density graphs attaining the value of 42% on random graphs of edge-density 0.7 on 64 vertices.
Weak Bipolarizable Graphs, Stephan Olariu
Weak Bipolarizable Graphs, Stephan Olariu
Computer Science Faculty Publications
We characterize a new class of perfectly orderable graphs and give a polynomial-time recognition algorithm, together with linear-time optimization algorithms for this class of graphs.