#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <math.h>

using namespace std;

ifstream f("date.in");
ofstream g("date.out");



bool fct(int i)
{   return i>=9.5;

}

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