#include <bits/stdc++.h> using namespace std ; int main () { double x , y , r , a , b ; int n , cnt = 0 ; cin >> n >> x >> y >> r ; while ( n -- ) { cin >> a >> b ; if ( ( double ) ( sqrt ( (x-a)*(x-a) + (y-b)*(y-b) ) ) <= r ) cnt ++ ; } cout << cnt ; }