#include <iostream>
#include <math.h>
using namespace std;
float dist(int Xa, int Ya, int Xb, int Yb){
    int sq1 = Xb-Xa;
    int sq2 = Yb-Ya;
    return sqrt(sq1*sq1 + sq2*sq2);
}
bool isIn(int Xa, int Ya, int Xb, int Yb, int R){
    if(dist(Xa,Ya,Xb,Yb) <= (float)R) return 1;
    else return false;
}
int main(){
    int counter = 0;
    int n, Xo, Yo, R;
    cin >> n >> Xo >> Yo >> R;
    for(int i = 0; i < n; ++i){
        int Xa, Ya;
        cin >> Xa >> Ya;
        if(isIn(Xo, Yo, Xa, Ya, R)) counter++;
    }
    cout << counter;
    return 0;
}