#include <iostream>
#include <vector>
#include <cmath>

using namespace std;

int main() {
	int n;
	cin >> n;
	
	int X, Y, R;
	cin >> X >> Y >> R;
	
	vector<pair<int, int>> points(n);
	for (int i = 0; i < n; ++i) {
		cin >> points[i].first >> points[i].second;
	}
	
	int count = 0;
	for (int i = 0; i < n; ++i) {
		int x = points[i].first;
		int y = points[i].second;
		double distance = sqrt((x - X) * (x - X) + (y - Y) * (y - Y));
		if (distance <= R) {
			count++;
		}
	}
	
	cout << count << endl;
	
	return 0;
}