The Two Paths Problem
نویسنده
چکیده
Given an undirected graph G = (V,E) and vertices slytl;s2,t2 , the problem is to determine whether or not G admits two vertex disjoint paths Pl and P2 ) connecting sl with tl and s2 with t2 respectively. This problem is solved by an O(n.m) algorithm (n = IV1 , m = IEI) , An important by-product of the paper is a theorem that states that if G is )+-connected and non-planar, then such paths pl and P2 exist for any choice of s1 t s2 j tl , and t2 , (as was conjectured by Watkins in [WI). \
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