C++ Tarjan 算法详解：点双连通分量与割点

先放代码。

#include <bits/stdc++.h>
  std;
  N = , M = ; 
 head[N], ver[M * ], Next[M * ]; 
 cut[N]; 
 dfn[N], low[N], st[N]; 
 n, m, tot = , num, root, top, cnt; 
vector<> dcc[N * ]; 

{
    ver[++tot] = y, Next[tot] = head[x], head[x] = tot;
}


{
    dfn[x] = low[x] = ++num;
    st[++top] = x;

     (x == root && head[x] == ) {
        dcc[++cnt].(x);
        ;
    }

     flag = ;
     ( i = head[x]; i; i = Next[i]) {
         y = ver[i];
         (!dfn[y]) {
            (y);
            low[x] = (low[x], low[y]);
             (low[y] >= dfn[x]) {
                flag++;
                 (x != root || flag > ) cut[x] = ;
                cnt++;
                 z;
                 {
                    z = st[top--];
                    dcc[cnt].(z);
                }  (z != y);
                dcc[cnt].(x);
            }
        }  {
            low[x] = (low[x], dfn[y]);
        }
    }
}

{
    ios::();
    cin.();
    cin >> n >> m;
     ( i = ; i <= m; i++) {
         x, y;
        cin >> x >> y;
         (x == y) ;
        (x, y), (y, x);
    }
     ( i = ; i <= n; i++) {
         (!dfn[i]) root = i, (i);
    }
    cout << cnt << ;
     ( i = ; i <= cnt; i++) {
        cout << dcc[i].();
         ( j = ; j < dcc[i].(); j++) cout <<  << dcc[i][j];
        cout << ;
    }
     ;
}