func_code_string: #include <bits/stdc++.h>   using namespace std;   pair<long double, int> v[100005];   int n;   long double minn = 2 * 3.14159265358979323846264338327950288419716939937510 + 1;   int minPos;   int main() {     cin >> n;     for (int i = 1; i <= n; i++) {       int x, y;       cin >> x >> y;       long double angle = atan2l(y, x);       v[i] = {           angle >= 0               ? angle               : angle + 2 * 3.14159265358979323846264338327950288419716939937510,           i};     }     sort(v + 1, v + n + 1);     for (int i = 1; i < n; i++) {       if (v[i + 1].first - v[i].first < minn) {         minn = v[i + 1].first - v[i].first;         minPos = i;       }     }     if (2 * 3.14159265358979323846264338327950288419716939937510 - v[n].first +             v[1].first <         minn) {       minn = 2 * 3.14159265358979323846264338327950288419716939937510 -              v[n].first + v[1].first;       minPos = n;     }     cout << v[minPos].second <<     << v[(minPos == n) ? 1 : (minPos + 1)].second;   }   