func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     ((void)0);     ((void)0);     ((void)0);     int T, N, M1, M2, s, e;     long long X;     for (cin >> T; T--;) {       M1 = M2 = 0x7fffffff;       s = 0;       e = 1e9;       for (cin >> N >> X; N--;) {         int d, h;         cin >> d >> h;         M1 = min(M1, -d);         M2 = min(M2, h - d);       }       if (X + M1 <= 0) {         cout <<  1 n ;         continue;       }       while (s <= e) {         int m = (s + e) >> 1;         if (X + 1LL * m * M2 + M1 <= 0)           e = m - 1;         else           s = m + 1;       }       if (s > 1e9)         cout <<  -1 n ;       else         cout << s + 1 <<   n ;     }     return 0;   }   