import java.io.*;
import java.util.*;

public class Solution
{
    public static void main(String[] args)
	{
        Scanner readIn = new Scanner(System.in);
		int n = readIn.nextInt();
		int x = readIn.nextInt();
		int y = readIn.nextInt();
		
		ArrayList<City> cities = new ArrayList<>(n);
		for(int ii = 0; ii < n; ii++)
			cities.add(new City(readIn.nextInt(), readIn.nextInt(), readIn.nextInt(), readIn.nextInt()));
		
		Collections.sort(cities);
		
		int outMax = cities.get(n - 1).points;
		for(int ii = n - 2; ii >= 0; ii--)
		{
			City current = cities.get(ii);
			int additionalPoints = 0;
			for(int jj = ii + 1; jj < n; jj++)
			{
				City next = cities.get(jj);
				if(Math.abs(next.lattitude - current.lattitude) <= x && Math.abs(next.longitude - current.longitude) <= x && next.points > additionalPoints)
					additionalPoints = next.points;
				if(additionalPoints == outMax)
					break;
			}
			current.points += additionalPoints;
			outMax = outMax > current.points ? outMax : current.points;
		}
		
		System.out.println(outMax);
    }
}

class City implements Comparable<City>
{
	public int lattitude;
	public int longitude;
	public int height;
	public int points;
	
	public City(int la, int lo, int height, int points)
	{
		this.lattitude = la;
		this.longitude = lo;
		this.height = height;
		this.points = points;
	}
	
	public int compareTo(City other)
	{
		return this.height - other.height;
	}
}