func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 404040;   int cnt, cnt2, cnt3, h, n, m;   struct Node {     int x, y, w, d, i;   } a[N];   bool cmp(Node x, Node y) { return x.d < y.d; }   vector<int> s[N];   vector<pair<int, int> > ss[N];   int dfn[N], low[N], viss[N], q[N], color[N], as[N];   map<int, int> sum, vis;   void jiantu(int x, int y) { s[x].push_back(y); }   void tarjan(int x) {     int c, i, y;     q[h++] = x, viss[x] = 1;     dfn[x] = low[x] = ++cnt2;     c = s[x].size();     for (i = 0; i < c; i++) {       y = s[x][i];       if (!dfn[y])         tarjan(y), low[x] = min(low[x], low[y]);       else if (viss[y])         low[x] = min(low[x], dfn[y]);     }     if (low[x] == dfn[x]) {       cnt3++;       while (1) {         h--;         color[q[h]] = cnt3;         viss[q[h]] = 0;         if (q[h] == x) {           q[h] = 0;           break;         }         q[h] = 0;       }     }   }   int check(int x) {     int i, ans = 1;     for (i = x + 1; i <= m; i++) jiantu(i + i, i + i - 1);     cnt2 = 0, cnt3 = 0;     memset(dfn, 0, sizeof(dfn));     memset(low, 0, sizeof(low));     memset(viss, 0, sizeof(viss));     memset(color, 0, sizeof(color));     for (i = 1; i <= cnt; i++)       if (!dfn[i]) h = 0, tarjan(i);     for (i = 1; i <= m; i++)       if (color[i + i - 1] == color[i + i]) ans = 0;     for (i = x + 1; i <= m; i++) s[i + i].pop_back();     return ans;   }   int erf(int l, int r) {     while (l <= r) {       int mid = l + r >> 1;       if (check(mid))         r = mid - 1;       else         l = mid + 1;     }     return l;   }   void init() {     int c, i, y, j, pl;     cnt = m + m;     for (i = 1; i <= n; i++) {       c = ss[i].size();       for (j = 0; j < c; j++) {         y = ss[i][j].first;         pl = ss[i][j].second;         sum[a[pl].w]++;         if (sum[a[pl].w] == 3) {           puts( No );           exit(0);         } else if (sum[a[pl].w] == 2) {           jiantu(vis[a[pl].w] * 2 - 1, pl + pl);           jiantu(pl + pl - 1, vis[a[pl].w] * 2);         }         vis[a[pl].w] = pl;       }       for (j = 0; j < c; j++) sum[a[ss[i][j].second].w]--;       for (j = 0; j < c; j++) {         y = ss[i][j].second;         if (j != c - 1) {           cnt++;           if (j != 0) jiantu(cnt, cnt - 1);           jiantu(cnt, y + y - 1);         }         if (j != 0) {           if (j != c - 1)             jiantu(y + y, cnt - 1);           else             jiantu(y + y, cnt);         }       }       for (j = c - 1; j >= 0; j--) {         y = ss[i][j].second;         if (j != 0) {           cnt++;           jiantu(cnt, y + y - 1);           if (j != c - 1) jiantu(cnt, cnt - 1);         }         if (j != c - 1) {           if (j != 0)             jiantu(y + y, cnt - 1);           else             jiantu(y + y, cnt);         }       }     }   }   int main() {     int i, ans, cnt;     scanf( %d%d , &n, &m);     for (i = 1; i <= m; i++)       scanf( %d%d%d%d , &a[i].x, &a[i].y, &a[i].w, &a[i].d), a[i].i = i;     sort(a + 1, a + m + 1, cmp);     for (i = 1; i <= m; i++)       ss[a[i].x].push_back(make_pair(a[i].y, i)),           ss[a[i].y].push_back(make_pair(a[i].x, i));     init();     ans = erf(0, m);     if (!check(ans)) {       puts( No );       return 0;     }     puts( Yes );     cnt = 0;     for (i = 1; i <= m; i++)       if (color[i + i - 1] > color[i + i]) as[++cnt] = a[i].i;     printf( %d %d n , a[ans].d, cnt);     for (i = 1; i <= cnt; i++) printf( %d  , as[i]);     return 0;   }   