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];
    int total = 0;
    for (int i = 0; i < n; i++) {
      cities[i] = new City(in.nextInt(), in.nextInt(), in.nextInt(), in.nextInt());
      if (i > 0) {
        if (cities[i].lat - cities[i - 1].lat <= x && cities[i].lon - cities[i - 1].lon <= y) {
          total += cities[i].p;
          System.err.println("New total = " + total);
          cities[i].vis = true;
        }
      } else {
        total += cities[i].p;
      }
    }
    System.out.println(total);
  }
}

class City implements Comparable<City> {
  int lat;
  int lon;
  int h;
  int p;
  boolean vis;
  
  City(int lat, int lon, int h, int p) {
    this.lat = lat;
    this.lon = lon;
    this.h = h;
    this.p = p;
    this.vis = false;
  }
  
  public int compareTo(City compareCity) {
		int height = ((City) compareCity).h;
		return this.h - height;
	}
}