func_code_string: #include <bits/stdc++.h>   using namespace std;   int x[20005];   int y[20005];   int main() {     int n;     scanf( %d , &n);     for (int i = 0; i < n; i++) {       int xx, yy;       scanf( %d %d , &xx, &yy);       x[xx + 10000]++;       y[yy + 10000]++;     }     long long ret = 0, sumx = 0, sumy = 0, tx = 0, ty = 0, dx = 0, dy = 0;     for (int i = 0; i <= 20000; i++) {       ret += (long long)x[i] * tx;       ret += (long long)y[i] * ty;       dx += sumx;       dy += sumy;       sumx += x[i];       sumy += y[i];       dx += sumx;       dy += sumy;       tx += dx;       ty += dy;     }     cout << ret << endl;     return 0;   }   