#include <bits/stdc++.h>

using namespace std;

#define MAX_N 50001

struct oaie{
  int x, y, xparcela, yparcela;
};

oaie o[MAX_N];
int x[MAX_N], y[MAX_N], ldir[4] = { 0, 1, 1, 0}, cdir[4] = { 0, 0, 1, 1 };

int cmp( oaie a, oaie b ){
  if( a.xparcela != b.xparcela )
    return a.xparcela < b.xparcela;
  return a.yparcela < b.yparcela;
}

int main(){
  ifstream cin( "ograzi.in" );
  ofstream cout( "ograzi.out" );
  int n, m, w, h, ans, i, j, k, lin, col, d, st, dr, mid;
  cin >> n >> m >> w >> h;
  for( i = 0; i < n; i++ ){
    cin >> x[i] >> y[i];
  }
  h++;
  w++;
  for( i = 0; i < m; i++ ){
    cin >> o[i].x >> o[i].y;
    o[i].xparcela = o[i].x / w;
    o[i].yparcela = o[i].y / h;
  }
  sort( o, o + n, cmp );
  ans = 0;
  for( i = 0; i < n; i++ ){
    for( d = 0; d < 4; d++ ){
      lin = x[i] + w * ldir[d];
      col = y[i] + h * cdir[d];
      lin /= w;
      col /= h;
      st = -1;
      dr = n;
      //printf("a");
      while( dr - st > 1 ){
    //    printf( "%d %d\n", st, dr);
        mid = ( dr + st ) / 2;
        if( o[mid].xparcela < lin || ( o[mid].xparcela == lin && o[mid].yparcela < col ) )
          st = mid;
        else
          dr = mid;
      }
      j = dr;
      st = -1;
      dr = n;
      while( dr - st > 1 ){
        mid = ( st + dr ) / 2;
        if( o[mid].xparcela < lin || ( o[mid].xparcela == lin &&  o[mid].yparcela <= col ) )
          st = mid;
        else
          dr = mid;
      }
     // cout << j << " " << st << "\n";
      for( ; j <= st; j++ ){
        if( o[j].x >= x[i] && o[j].x < x[i] + w && o[j].y >= y[i] && o[j].y < y[i] + h ){
          ans++;
        //  cout << j << " " << i << "\n";
        }
      }
    }
  }
  cout << ans;
    return 0;
}