func_code_string: #include <bits/stdc++.h>   using namespace std;   map<int, int> sg;   map<int, bool> us;   int main() {     int n;     cin >> n;     for (int i = 1; i <= n; i++) {       int x, d;       cin >> x >> d;       sg[x] = x + d;       us[x] = true;       if (us[x + d] && sg[x + d] == x && sg[x] == x + d) {         cout <<  YES n ;         return 0;       }     }     cout <<  NO ;   }   