#include <iostream>

using namespace std;

int main()
{
    int n,xc,yc,r,i,x,y,nr=0;
    cin>>n>>xc>>yc>>r;
    for(i=1;i<=n;i++)
    {
        cin>>x>>y;
        x=x-xc;
        y=y-yc;
        x=x*x;
        y=y*y;
        x=x+y;
        if(x<r*r)
            nr++;
    }
    cout<<nr<<'\n';
    return 0;
}