func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, x, y, a = 0, b = 0;     cin >> n;     vector<pair<int, int>> v;     while (n--) {       cin >> x >> y;       a += x;       b += y;       v.push_back(make_pair(x, y));     }     bool ok = 0;     if (a % 2 == 0 && b % 2 == 0) {       cout << 0;       return 0;     }     if (a % 2 && b % 2) {       for (auto i : v) {         if ((i.first % 2 == 0 && i.second % 2) ||             (i.first % 2 && i.second % 2 == 0)) {           ok = 1;           break;         }       }     }     cout << (ok ? 1 : -1);   }   