COLORCODING
Color-coding
In computer science and graph theory, the method of color-coding efficiently finds k-vertex simple paths, k-vertex cycles, and other small subgraphs within a given graph using probabilistic algorithms, which can then be derandomized and turned into deterministic algorithms. This method shows that many subcases of the subgraph isomorphism problem can in fact be solved in polynomial time.The above text is a snippet from Wikipedia: Color-coding
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