#include <bits/stdc++.h>
 
#define pb push_back
#define mp make_pair
#define mod 1000000007
#define PI 3.141592653589793;
 
using namespace std;

int n,x,y,r,a,b,res;
double dist;

int main() {
    //freopen("data.in", "r", stdin);
    //freopen("data.out", "w", stdout);

    scanf("%d%d%d%d", &n, &x, &y, &r);

    for(int i= 0; i<n; i++){
        scanf("%d%d", &a, &b);
        dist = (x - a)*(x - a);
        dist += (y - b)*(y - b);
        if(sqrt(dist) <= double(r)) res++;
    }

    cout<<res;
}