func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e6 + 11;   int a[N], b[N];   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n, m;     cin >> n >> m;     for (int i = 1; i <= m; i++) {       cin >> a[i] >> b[i];     }     vector<int> v;     for (int p = 1; p <= 200; p++) {       int x = 0;       for (int i = 1; i <= m; i++) {         int d = (a[i] / p);         if (a[i] % p != 0) d++;         if (b[i] != d) {           x = 1;           break;         }       }       if (x == 0) {         int d = (n / p);         if (n % p != 0) d++;         v.push_back(d);       }     }     sort(v.begin(), v.end());     if (v[0] != v[v.size() - 1]) {       cout << -1 << endl;     } else       cout << v[0] << endl;   }   