#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(i, a, n) for (int i = (a); i < (n); i++)
#define per(i, a, n) for (int i = (n) - 1; i >= (a); i--)
#define FOR(i, n) rep(i, a, (n))

template<class T>
struct Point {
	typedef Point P;
	T x, y;
	explicit Point(T _x=0, T _y=0) : x(_x), y(_y) {}
	T dist2() const { return x*x + y*y; }
};

using P = Point<double>;

vector<double> quad(double a, double b, double c) {
	double D = b*b - 4*a*c;
	if (D < 0) {
		return {};
	} else {
		return {
			(-b - sqrt(D)) / (2*a),
			(-b + sqrt(D)) / (2*a)
		};
	}
}

double EPS = 1e-5;

int main(void)
{
	ios_base::sync_with_stdio(false);
	int n;
	double r;
	P l;
	cin >> n >> r >> l.x >> l.y;
	vector<P> a(n);
	rep(i,0,n) cin >> a[i].x >> a[i].y;
	
	r += EPS;

	vector<pair<double,int>> events;

	rep(i,0,n) {
		vector<double> sols = quad(
				l.dist2(),
				-2 * (l.x * a[i].x + l.y * a[i].y),
				a[i].dist2() - r*r
				);
		if (!sols.empty()) {
			events.push_back({sols[0] - EPS, +1});
			events.push_back({sols[1] + EPS, -1});
		}
	}
	sort(events.begin(), events.end());

	int res = 0;
	int cur = 0;
	for (auto& e : events) {
		res = max(res,cur);
		cur += e.second;
		res = max(res,cur);
	}

	cout << res << endl;
	return 0;
}