#include <bits/stdc++.h>

using namespace std;

int main()
{
  int N;
  while(cin >> N, N){
    int W, H;
    int field[101][101] = {{0}};
    cin >> W >> H;
    for(int i = 0; i < N; i++){
      int x, y;
      cin >> x >> y;
      x--, y--;
      field[x][y] = 1;
    }
    int S, T;
    cin >> S >> T;
    int ans = 0;
    for(int i = 0; i <= W - S; i++){
      for(int j = 0; j <= H - T; j++){
	int cnt = 0;
	for(int s = 0; s < S; s++){
	  for(int t = 0; t < T; t++){
	    cnt += field[i + s][j + t];
	  }
	}
	ans = max(ans, cnt);
      }
    }
    cout << ans << endl;
  }
  return 0;
}