【模板】Tarjan（强连通、桥、割点）

 1 void Tarjan(int u,int inedge){
 2     dfn[u] = low[u] = ++dfn_clock;
 3     for(int i = h[u];i!=-1;i = e[i].nex){
 4         int v = e[i].to;
 5         if(!dfn[v]){
 6             Tarjan(v,i);
 7             low[u] = min(low[u],low[v]);
 8             if(low[v] > dfn[u]) bridge[i] = bridge[i^1] = 1;
 9         }
10         else if( i != (inedge^1) ) low[u] = min(low[u],dfn[v]);
11     }
12 }