A connected graph G,all of whose blocks are cliques or complete bipartite graphs,is called a clique-bipartite graph.Let D(G)be its distance matrix.By a theorem of Graham et al,it is proved that det(D(G))≠0 if and only if K2,2 is not a block of G in this paper.Furthermore,the formula for the determinant and inverse of D(G)are given.
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