import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int x = in.nextInt();
		int y = in.nextInt();
		City[] cities = new City[n];
		for (int i = 0; i < n; i++) {
			int latitude = in.nextInt();
			int longitude = in.nextInt();
			int height = in.nextInt();
			int points = in.nextInt();
			cities[i] = new City(latitude, longitude, height, points);
		}
		solve(cities, x, y);
	}

	private static void solve(City[] cities, int x, int y) {
		System.out.println(maxSubArraySum(cities, x, y));

	}

	static int maxSubArraySum(City a[], int x, int y) {
		int size = a.length;
		int max_so_far = Integer.MIN_VALUE, max_ending_here = 0;

		for (int i = 0; i < size; i++) {
			max_ending_here = max_ending_here + a[i].points;
			if (max_so_far < max_ending_here)
				max_so_far = max_ending_here;
			if (max_ending_here < 0 || (i > 0 && (areTooFar(a[i], a[i - 1], x, y))))
				max_ending_here = 0;
		}
		return max_so_far;
	}

	private static boolean areTooFar(City city1, City city2, int x, int y) {
		// TODO Auto-generated method stub
		return Math.abs(city2.latitude - city1.latitude) > x || Math.abs(city1.longitude - city2.longitude) > y;
	}
}

class City implements Comparable<City> {
	int latitude, longitude, height, points;

	public City(int latitude, int longitude, int height, int points) {
		this.latitude = latitude;
		this.longitude = longitude;
		this.points = points;
		this.height = height;
	}

	@Override
	public int compareTo(City o) {

		return this.height = o.height;
	}

}