1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 #include <vector> 5  6 using namespace std; 7 #define MAXN 1000 8 int low[MAXN],visit[MAXN]; // low[i] = min(visit[i],visist[j],low[w]); j 是 回路的父值，w是儿子值 9 int pointNum,edgeNum;10 int count; // 统计遍历的顺序11 12 int dfsArticul(vector<vector<int> > G,int v0) { // 最小的low[]值13     int min = visit[v0] = ++count;14     for (int i = 0;i < G[v0].size();i++) {15         int w = G[v0][i];16         if (visit[w] == 0) {17             low[w] = dfsArticul(G,w);18             if (low[w] < min) min = low[w];19             if (low[w] >= visit[v0]) cout << v0 << endl;20         }21         else if (visit[w] < min) {22             min = visit[w];23         }24     }25     return low[v0] = min;26 }27 28 void findArticul(vector <vector<int> > G) { 29     visit[0] = 1;30     count = 1;31     for (int i = 1;i < pointNum;i++) {32         visit[i] = 0;33     }34     int p = G[0][0];35     dfsArticul(G,p);36     if (count < pointNum) { // 父节点是否有两个子树37         cout << p << endl;38         for (int i = 1;i < G[0].size();i++) {39             int w = G[0][i];40             if (visit[w] == 0)41                 dfsArticul(G,w);42         }43     }44 }45 46 int main () {47     // freopen("1.in","r",stdin);48     vector <vector<int> > G; // 邻接表49     cin >> pointNum >> edgeNum; // 点的个数，边的个数50     G.resize(pointNum + 1);51     for (int i = 0;i < pointNum;i++) G[i].clear();52     for (int i = 0;i < edgeNum;i++) {53         int x,y;54         cin >> x >> y; // 边的起点，和终点55         G[x].push_back(y);56         G[y].push_back(x);57     }58     findArticul(G);59 }