#include <iostream>

using namespace std;

int dist, x1, x2, y1, y2, r, n, rez, i;

bool e_inauntru()
{
    dist = (x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1);

    if(dist <= r * r)
        return 1;
    return 0;
}

int main()
{
    cin >> n >> x1 >> y1 >> r;

    for(i = 1; i <= n; i++)
    {
        cin >> x2 >> y2;

        if(e_inauntru())
            rez++;
    }

    cout << rez;
}