#include <bits/stdc++.h>

using namespace std;

int main() {
	int n, x, y, r, pointsInside = 0;
	cin >> n >> x >> y >> r;
	while (n--) {
		int x1, y1;
		cin >> x1 >> y1;
		if ((x1 - x) * (x1 - x) + (y1 - y) * (y1 - y)  <= r * r) {
			++pointsInside;
		} 
	}
	cout << pointsInside << '\n';
	return 0;
}