func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAXN = 1000005;   int N, M, dx, dy;   int xidx[MAXN];   int cnt[MAXN];   int ans[MAXN][2];   int main() {     cin >> N >> M >> dx >> dy;     for (int i = 0; i < N; i++) xidx[((long long)i * dx) % N] = i;     for (int i = 0; i < M; i++) {       int x, y;       cin >> x >> y;       int val = (y - (long long)xidx[x] * dy) % N;       if (val < 0) val += N;       cnt[val]++;       ans[val][0] = x, ans[val][1] = y;     }     int best = 0;     for (int i = 1; i < N; i++)       if (cnt[best] < cnt[i]) best = i;     cout << ans[best][0] <<     << ans[best][1] <<   n ;     return 0;   }   