#include <iostream>

using namespace std;

int main() {
	int N, x, y, r, xi, yi;
	cin >> N >> x >> y >> r;
	r *= r;
	int counter = 0;

	while (N--) {
		cin >> xi >> yi;
		if ((xi-x)*(xi-x) + (yi-y)*(yi-y) <= r) counter++;
	}

	cout << counter;

	return 0;
}