XU Bao-gang conjectured: If the clique complex C(G) of a graph G is acyclic, G is contractible. In this paper we prove that the conjecture holds for planar graphs.是什么意思_XU Bao-gang conjectured: If the clique complex C(G) of a graph G is acyclic, G is contractible. In this paper we prove that the conjecture holds for planar graphs.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句