func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 2001;   const int INF = 1e9 + 1;   struct T {     int u, f, w, num;     T(int u, int f, int w, int num) : u(u), f(f), w(w), num(num){};     T(){};   };   vector<T> G[N];   int n, m, s, t;   bool used[N];   bool ist[N];   int parent[N];   pair<int, pair<int, int> > ans;   pair<int, int> mn;   int Time = 0;   int tin[N];   int fin[N];   void dfs(int v) {     used[v] = true;     for (int i = 0; i < G[v].size(); ++i) {       int to = G[v][i].u;       if (used[to] == false && G[v][i].f == 1) {         parent[to] = v;         dfs(to);       }     }   }   vector<int> getPath(int s, int t) {     memset(used, false, sizeof(used));     vector<int> ans;     dfs(s);     if (used[t] == false) return ans;     int v = t;     while (v != s) {       ans.push_back(v);       v = parent[v];     }     ans.push_back(v);     return ans;   }   void DeleteEdge(int v, int u, int& num) {     for (int i = 0; i < G[v].size(); ++i) {       if (G[v][i].u == u) {         G[v][i].f = 0;         num = i;         break;       }     }     for (int i = 0; i < G[u].size(); ++i) {       if (G[u][i].u == v) {         G[u][i].f = 0;         break;       }     }   }   void AddEdge(int v, int u) {     for (int i = 0; i < G[v].size(); ++i) {       if (G[v][i].u == u) {         G[v][i].f = 1;         break;       }     }     for (int i = 0; i < G[u].size(); ++i) {       if (G[u][i].u == v) {         G[u][i].f = 1;         break;       }     }   }   void update(int weight, pair<int, int> num) {     if (ans.first == -1 || weight < ans.first) {       ans.first = weight;       ans.second = num;     }   }   void findMinBridge(int v, int num) {     if (v == t) ist[v] = true;     used[v] = true;     Time++;     tin[v] = Time;     fin[v] = Time;     for (int i = 0; i < G[v].size(); ++i) {       int to = G[v][i].u;       if (G[v][i].num == num || G[v][i].f == 0) continue;       if (used[to] == true) {         fin[v] = min(fin[v], tin[to]);       } else {         findMinBridge(to, G[v][i].num);         ist[v] |= ist[to];         fin[v] = min(fin[v], fin[to]);         if (fin[to] > tin[v] && ist[to] == true) {           if (mn.first > G[v][i].w) {             mn.first = G[v][i].w;             mn.second = G[v][i].num;           }         }       }     }   }   int main() {     ans.first = -1;     scanf( %d%d%d%d , &n, &m, &s, &t);     s--;     t--;     for (int i = 0; i < m; ++i) {       int u, v, w;       scanf( %d%d%d , &u, &v, &w);       u--;       v--;       G[u].push_back(T(v, 1, w, i));       G[v].push_back(T(u, 1, w, i));     }     vector<int> path = getPath(s, t);     if (path.size() == 0) {       printf( 0 n0 n );       return 0;     }     for (int i = (int)path.size() - 1; i > 0; --i) {       int num;       DeleteEdge(path[i], path[i - 1], num);       vector<int> tmp = getPath(s, t);       if (tmp.size() == 0) {         update(G[path[i]][num].w, make_pair(G[path[i]][num].num, -1));       } else {         memset(used, false, sizeof(used));         memset(ist, false, sizeof(ist));         mn.first = INF;         Time = 0;         findMinBridge(s, -1);         if (mn.first != INF)           update(G[path[i]][num].w + mn.first,                  make_pair(G[path[i]][num].num, mn.second));       }       AddEdge(path[i], path[i - 1]);     }     if (ans.first == -1) {       printf( -1 n );       return 0;     }     printf( %d n , ans.first);     if (ans.second.second == -1) {       printf( 1 n%d , ans.second.first + 1);     } else {       printf( 2 n%d %d n , ans.second.first + 1, ans.second.second + 1);     }     return 0;   }   