#include<stdio.h>
#define mmax 1000
int a[mmax][mmax],n,m,w,h;

int main()
{int i,j,k,x,y,s=0;
freopen("ograzi.in","r",stdin);
freopen("ograzi.out","w",stdout);
scanf("%d%d%d%d",&n,&m,&w,&h);
for(i=0;i<n;++i)
	{scanf("%d%d",&x,&y);
	 for(j=x;j<=x+w;++j)
	 	for(k=y;k<=y+h;++k)
	 		a[j][k]=1;}
	 		
for(i=0;i<m;++i)
	{scanf("%d%d",&x,&y);
	 if(a[x][y])++s;}
printf("%d\n",s);
fclose(stdin);
fclose(stdout);
return 0;}