func_code_string: #include <bits/stdc++.h>   using namespace std;   int px, py;   int tx, ty;   int decide(int x, int y, int x2, int y2) {     px = tx;     py = ty;     px -= x;     py -= y;     x2 -= x;     y2 -= y;     int dis = x2 * py - y2 * px;     return dis >= 0;   }   int main() {     int n, d;     cin >> n >> d;     int ele;     cin >> ele;     while (ele--) {       int cnt = 0;       cin >> tx >> ty;       cnt += decide(d, 0, n, n - d);       cnt += decide(n, n - d, n - d, n);       cnt += decide(n - d, n, 0, d);       cnt += decide(0, d, d, 0);       if (cnt == 4)         printf( YES n );       else         printf( NO n );     }   }   