func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1010, M = 200200;   int i, j, k, n, m, ch, now, q;   int a[N][N], ans[M];   struct cc {     int x, y;   } A[M];   struct dd {     int l, r, s, t, q;   } Q[M];   void R(int &x) {     x = 0;     ch = getchar();     while (ch <  0  ||  9  < ch) ch = getchar();     while ( 0  <= ch && ch <=  9 ) x = x * 10 + ch -  0 , ch = getchar();   }   bool cmp(const dd &a, const dd &b) { return a.r < b.r; }   void work() {     now++;     int x = A[now].x, y = A[now].y;     a[x][y] = a[y][x] = now;     for (int i = 1; i <= n; i++) a[x][i] = a[y][i] = max(a[x][i], a[y][i]);   }   int main() {     R(n);     R(m);     R(q);     for (i = 1; i <= m; i++) R(A[i].x), R(A[i].y);     for (i = 1; i <= q; i++) {       R(Q[i].l);       R(Q[i].r);       R(Q[i].s);       R(Q[i].t);       Q[i].q = i;     }     sort(Q + 1, Q + q + 1, cmp);     now = 0;     for (i = 1; i <= q; i++) {       while (now < Q[i].r) work();       if (a[Q[i].t][Q[i].s] >= Q[i].l) ans[Q[i].q] = 1;     }     for (i = 1; i <= q; i++) {       if (ans[i])         puts( Yes );       else         puts( No );     }   }   