摘要：数据结构 dfn[i] :编号为i的结点在dfs遍历图的过程中的访问序号（开始时间） low[i] :从i结点出发dfs过程中i下方的结点能到达的最早的当前搜索路径上的结点的开始时间。（初始时 low[i]=dfn[i] ） 操作 遍历结点没被访问过的就开始dfs，碰到哪个结点哪个结点就入栈，栈中结 阅读全文

摘要：描述 Caocao was defeated by Zhuge Liang and ZhouYu in the battle of Chibi. But he wouldn't give up. Caocao's army still was not good at water battles, s 阅读全文

摘要：描述 In order to make their sons brave, Jiajia and Wind take them to a big cave. The cave has n rooms, and one-way corridors connecting some rooms. Each 阅读全文