BZOJ 1656: [Usaco2006 Jan] The Grove 树木(神奇的bfs之射线法)Apr 15, 2016·3 minsACM Bfs 射线法 计算几何1656: [Usaco2006 Jan] The Grove 树木 # Time Limit: 5 Sec Memory Limit: 64 MB Submit: 143 Solved: 88 [Submit][Status][Discuss]