func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     int xs[200000], ys[200000];     cin >> n;     for (int i = 0; i < n; i++) {       cin >> xs[i] >> ys[i];     }     map<int, int> vert, hor;     for (int i = 0; i < n; i++) {       int x, y;       x = xs[i];       y = ys[i];       int v = x - y + 1;       int h = y + x - 1;       int buf;       buf = vert[v];       vert[v] = buf + 1;       buf = hor[h];       hor[h] = buf + 1;     }     long long res = 0;     for (map<int, int>::iterator it = vert.begin(); it != vert.end(); ++it) {       long long buf = (long long)it->second;       buf--;       long long sum = (buf * buf + buf) / 2;       res += sum;     }     for (map<int, int>::iterator it = hor.begin(); it != hor.end(); ++it) {       long long buf = (long long)it->second;       buf--;       long long sum = (buf * buf + buf) / 2;       res += sum;     }     cout << res;   }   