摘要：
This problem is not quite difficult (a typical BFS traversal of graph), though, its aceptance rate is relatively low. In fact, the key obstacle in pas... 阅读全文
摘要：
This problem is an application of graph traversal, which has two systematic methods:Bread-First Search (BFS)andDepth-First Search (DFS). In the follow... 阅读全文
摘要：
To solve this problem, some observations have to be made first.Let's first see two relatively easy observations.To maximize the probability that we ca... 阅读全文