func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 5;   const long long int MXN = 1e18;   struct node {     double x, y;   } p, p1, p2, p3, p4;   double ji(node a, node b, node c) {     return (b.x - a.x) * (c.y - a.y) - (c.x - a.x) * (b.y - a.y);   }   bool jug(node a) {     if ((ji(p1, p2, a) * ji(p3, p4, a) >= 0) &&         (ji(p2, p3, a) * ji(p4, p1, a) >= 0))       return true;     return false;   }   int main() {     int n, d, m;     cin >> n >> d >> m;     p1.x = 0, p1.y = d;     p2.x = d, p2.y = 0;     p3.x = n, p3.y = n - d;     p4.x = n - d, p4.y = n;     int ans = 0;     double a, b;     for (int i = 0; i < m; i++) {       cin >> p.x >> p.y;       if (jug(p)) {         cout <<  YES  << endl;       } else         cout <<  NO  << endl;     }   }   