#include <cstdio>
using namespace std;
int main()
{
    int n, xc, yc, r, x, y,ans = 0;
    scanf("%d %d %d %d", &n, &xc, &yc, &r);
    for (int i = 1; i <= n; ++i)
    {
        scanf("%d %d", &x, &y);
        if ((x - xc) * (x - xc) + (y - yc) * (y - yc) <= r * r)
            ++ans;
    }
    printf("%d\n", ans);
    return 0;
}