func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long inf = 1e18;   const long long mod = 998244353;   const long long maxn = 5e4 + 10, maxval = 1e9 + 10, mlg = (1 << 18) + 10;   struct edge {     long long u, v, c, t;   } ed[maxn * 6];   long long n, m, cnt;   long long ans[maxn * 6], comp[maxn * 6], mark1[6 * maxn], mark2[6 * maxn];   vector<long long> ts, nei[maxn * 6][2], adj[maxn * 6];   map<long long, long long> mp;   long long N(long long x) {     if (x <= m) {       return x + m;     } else if (x <= 2 * m) {       return x - m;     } else if (x <= 4 * m) {       return x + 2 * m;     } else {       return x - 2 * m;     }   }   void add_con(long long x, long long y) {     long long nagh_x = N(x);     long long nagh_y = N(y);     nei[nagh_x][1].push_back(y);     nei[y][0].push_back(nagh_x);     nei[nagh_y][1].push_back(x);     nei[x][0].push_back(nagh_y);   }   void dfs1(long long u) {     mark1[u] = 1;     for (auto v : nei[u][1]) {       if (!mark1[v]) {         dfs1(v);       }     }     ts.push_back(u);   }   void dfs2(long long u) {     mark2[u] = 1;     comp[u] = cnt;     for (auto v : nei[u][0]) {       if (!mark2[v]) {         dfs2(v);       }     }   }   bool ch(long long x) {     long long tmp_cnt = 0;     cnt = 0;     for (int i = 0; i <= 6 * m; i++) {       nei[i][1].clear();       nei[i][0].clear();       comp[i] = 0;       mark1[i] = 0;       mark2[i] = 0;       ans[i] = 0;     }     for (int i = 0; i < m; i++) {       if (ed[i + 1].t > x) {         nei[i + 1][1].push_back(i + 1 + m);         nei[i + 1 + m][0].push_back(i + 1);       }     }     for (int i = 1; i <= n; i++) {       mp.clear();       for (int j = 0; j < adj[i].size(); j++) {         tmp_cnt++;         if (j > 0) {           add_con(N(2 * m + tmp_cnt - 1), N(adj[i][j]));           add_con(N(2 * m + tmp_cnt - 1), 2 * m + tmp_cnt);           add_con(N(adj[i][j]), 2 * m + tmp_cnt);         } else {           add_con(N(adj[i][j]), 2 * m + tmp_cnt);         }         if (!mp[ed[adj[i][j]].c]) {           mp[ed[adj[i][j]].c] = adj[i][j];         } else if (mp[ed[adj[i][j]].c] == -1) {           return false;         } else {           add_con(adj[i][j], mp[ed[adj[i][j]].c]);           mp[ed[adj[i][j]].c] = -1;         }       }     }     for (int i = 1; i <= 6 * m; i++) {       if (!mark1[i]) {         dfs1(i);       }     }     while (!ts.empty()) {       long long v = ts.back();       ts.pop_back();       if (!mark2[v]) {         cnt++;         dfs2(v);       }     }     for (int i = 1; i <= m; i++) {       if (comp[i] == comp[i + m]) {         return false;       }       if (comp[i] > comp[i + m]) {         ans[i] = 1;       } else {         ans[i] = 0;       }     }     for (int i = 2 * m + 1; i <= 4 * m; i++) {       if (comp[i] == comp[i + 2 * m]) {         return false;       }     }     return true;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     ;     cin >> n >> m;     for (int i = 0; i < m; i++) {       cin >> ed[i + 1].u >> ed[i + 1].v >> ed[i + 1].c >> ed[i + 1].t;       adj[ed[i + 1].u].push_back(i + 1);       adj[ed[i + 1].v].push_back(i + 1);     }     long long l = -1, r = inf;     while (r - l > 1) {       long long mid = (l + r) / 2;       if (ch(mid)) {         r = mid;       } else {         l = mid;       }     }     if (r == inf) {       cout <<  No  << endl;       return 0;     }     cout <<  Yes  << endl;     ch(r);     long long tmp = 0;     for (int i = 0; i < m; i++) {       if (ans[i + 1]) {         tmp++;       }     }     cout << r <<     << tmp << endl;     for (int i = 0; i < m; i++) {       if (ans[i + 1]) {         cout << i + 1 <<    ;       }     }     cout << endl;   }   