#include <iostream>
#include <math.h>
using namespace std;
int main(){
int N = 0, x = 0, y = 0, R = 0, d = 0, xi = 0, yi = 0, c = 0, i = 0;
cin >> N >> x >> y >> R;
while(N!=i){
cin >> xi >> yi;
if(x == 0 && y == 0){
    if((xi*xi) + (yi*yi) < (R*R) || ((xi*xi)+(yi*yi)) == (R*R) && !(xi*xi+yi*yi>R*R)){
        c++;
    }
}
if(x!=0 && y!=0){
    d = sqrt(((xi - x) * (xi - x)) + ((yi - y) * (yi - y)));
if((d*d < R * R) || (d*d==R*R) && x!=0 && y!=0){
    c++;
}
}

i++;
}

cout << c << endl;

}