A note on the complexity of graph parameters and the uniqueness of their realizations
نویسندگان
چکیده
Let ν be some graph parameter and let G be a class of graphs for which ν can be computed in polynomial time. In this situation it is often possible to devise a strategy to decide in polynomial time whether ν has a unique realization for some graph in G. We first give an informal description of the conditions that allow one to devise such a strategy, and then we demonstrate our approach for three well-known graph parameters: the domination number, the independence number, and the chromatic number.
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