#include<cstdio>
#include<vector>
using namespace std;
const int p1=1009;
const int p2=37193;
int H(int x,int y)
{
    return (x*p1+y)%p2;
}
vector<int>gx[p2+1];
vector<int>gy[p2+1];
int main()
{
    freopen("ograzi.in","r",stdin);
    freopen("ograzi.out","w",stdout);
    int n,m,w,h,i,x,y,x1,y1,j,nr=0;
    scanf("%d%d%d%d",&n,&m,&w,&h);
    for(i=1; i<=n; ++i)
    {
        scanf("%d%d",&x,&y);
        x1=x/h;
        y1=y/w;
        gx[H(x1,y1)].push_back(x);
        gy[H(x1,y1)].push_back(y);
    }
    for(i=1; i<=m; ++i)
    {
        scanf("%d%d",&x,&y);
        x1=x/h;
        y1=y/w;
        int val=H(x1,y1);
        bool ok=0;
        for(j=0; j<gx[val].size()&&j<gy[val].size(); ++j)
        {
            int vx=gx[val][j];
            int vy=gy[val][j];
            if((x-vx)*(x-vx-h)<=0&&(y-vy)*(y-vy-w)<=0)
            {
                nr++;
                ok=1;
                break;
            }
        }
        if(!ok)
        {
            x1=x/h-1;
            y1=y/w;
            val=H(x1,y1);
            for(j=0; j<gx[val].size()&&j<gy[val].size(); ++j)
            {
                int vx=gx[val][j];
                int vy=gy[val][j];
                if((x-vx)*(x-vx-h)<=0&&(y-vy)*(y-vy-w)<=0)
                {
                    nr++;
                    ok=1;
                    break;
                }
            }
        }
        if(!ok)
        {
            x1=x/h;
            y1=y/w-1;
            val=H(x1,y1);
            for(j=0; j<gx[val].size()&&j<gy[val].size(); ++j)
            {
                int vx=gx[val][j];
                int vy=gy[val][j];
                if((x-vx)*(x-vx-h)<=0&&(y-vy)*(y-vy-w)<=0)
                {
                    nr++;
                    ok=1;
                    break;
                }
            }
        }
        if(!ok)
        {
            x1=x/h-1;
            y1=y/w-1;
            val=H(x1,y1);
            for(j=0; j<gx[val].size()&&j<gy[val].size(); ++j)
            {
                int vx=gx[val][j];
                int vy=gy[val][j];
                if((x-vx)*(x-vx-h)<=0&&(y-vy)*(y-vy-w)<=0)
                {
                    nr++;
                    ok=1;
                    break;
                }
            }
        }
    }
    printf("%d\n",nr);
    return 0;
}