#include <iostream>
#include <math.h>
using namespace std;
int main(){

int N = 0, x = 0, y = 0, R = 0, i = 0, xi = 0, yi = 0, c = 0;
cin >> N >> x >> y >> R;
while(N!=i){
    cin >> xi >> yi;
    if(((xi-x) * (xi-x)) + ((yi-y) * (yi-y)) <= R*R){
        c++;
    }
i++;
}

cout << c;

}