POJ2553 SP1799 我们知道单独一个强连通分量中的所有点是满足题目要求的 但如果它连出去到了其他点那里,要么成为新的强连通分量,要么失去原有的符合题目要求的性质 所以只需tarjan缩点求出所有强连通分量,再O(E)枚举所有边,是否会成为连接一个分量与另一个分量的边--即一条出度--即可 如果一个分量没有出度,那么他中间的所有点都是符合题目要求的点 (因为快读快输加了太长所以就不贴了) const int N=5005,M=N*N>>1; int h[N],en,n,m,dfn[N]…

The Bottom of a Graph Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 11981   Accepted: 4931 Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finite set, its elements being called ve…

Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finite set, its elements being called vertices (or nodes). Let E be a subset of the Cartesian product V×V, its elements being called edges. Then G…

The Bottom of a Graph Time Limit : 6000/3000ms (Java/Other)   Memory Limit : 131072/65536K (Java/Other) Total Submission(s) : 1   Accepted Submission(s) : 1 Problem Description We will use the following (standard) definitions from graph theory. Let V…

本题分两步: 1 使用Tarjan算法求全部最大子强连通图.而且标志出来 2 然后遍历这些节点看是否有出射的边,没有的顶点所在的子强连通图的全部点,都是解集. Tarjan算法就是模板算法了. 这里使用一个数组和一个标识号,就能够记录这个顶点是属于哪个子强连通图的了. 然后使用DFS递归搜索全部点及其边,假设有边的还有一个顶点不属于本子强连通图.那么就说明有出射的边. 有难度的题目: #include <stdio.h> #include <stdlib.h> #include &…

题意: 求出度为0的强连通分量. 思路: 缩点 具体有两种实现: 1.遍历所有边, 边的两端点不在同一强连通分量的话, 将出发点所在强连通分量出度+1. #include <cstdio> #include <cstring> #include <stack> #include <algorithm> using namespace std; //0.03s 4856K const int MAXN = 5005; struct Pool { int pre…

The Bottom of a Graph Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 9139   Accepted: 3794 Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finite set, its elements being called ver…

题目地址:http://poj.org/problem?id=2553 The Bottom of a Graph Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 7881   Accepted: 3263 Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finit…

The Bottom of a Graph Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 9641   Accepted: 4008 Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finite set, its elements being called ver…

[POJ2553]The Bottom of a Graph Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 11182   Accepted: 4608 Description We will use the following (standard) definitions from graph theory. Let V be a nonempty and finite set, its elements being…