摘要：
Find the number connected component in the undirected graph. Each node in the graph contains a label and a list of its neighbors. (a connected compone 阅读全文
摘要：
Given two words (start and end), and a dictionary, find the length of shortest transformation sequence from start to end, such that: Notice Return 0 i 阅读全文
摘要：
Six degrees of separation is the theory that everyone and everything is six or fewer steps away, by way of introduction, from any other person in the 阅读全文