#include<cmath>
#include<cstdio>
using namespace std;

int N, ans;

double xc, yc, R, x, y, eps = 0.00001;

inline double distance(double x1, double y1, double x2, double y2){
    return sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
}

int main(){

scanf("%d %lf %lf %lf", &N, &xc, &yc, &R);

while(N--){
    scanf("%lf %lf", &x, &y);
    if(R - distance(xc, yc, x, y) >= eps) ans++;
}printf("%d", ans);

return 0;
}