#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

struct City{
    int latitude;
    int longitude;
    int height;
    int points;
    City(int a, int b, int c, int d){
        latitude = a;
        longitude = b;
        height = c;
        points = d;
    }
    friend bool operator<(const City &c1, const City &c2){
        if(c1.height == c2.height){
            if(c1.latitude == c2.latitude){
                if(c1.longitude == c2.longitude){
                    return c1.points < c2.points;
                }
                else
                    return c1.longitude < c2.longitude;
            }
            else
                return c1.latitude < c2.latitude;
        }
        else
            return c1.height < c2.height;
    }
};

int get_max(const vector<City> &cities, int x, int y){
    vector<int> max_points(cities.size(), 0);
    max_points[0] = cities[0].points;
    for(int i = 1; i < cities.size(); i++){
        for(int j = 0; j < i; j++){
            //Can jth city even reach ith city
            if(abs(cities[j].latitude - cities[i].latitude) <= x && abs(cities[j].longitude - cities[i].longitude) <= y){
                if(max_points[j] + cities[i].points > cities[i].points)
                    max_points[i] = max_points[j] + cities[i].points;
                else
                    max_points[i] = cities[i].points;
            }
            else
                max_points[i] = cities[i].points;   

        }
    }
    return *max_element(max_points.begin(), max_points.end());
}

int main(){
    int n;
    int x;
    int y;
    cin >> n >> x >> y;
    vector<City> cities;
    for(int a0 = 0; a0 < n; a0++){
        int latitude;
        int longitude;
        int height;
        int points;
        cin >> latitude >> longitude >> height >> points;
        City c(latitude, longitude, height, points);
        cities.push_back(c);
    }

    sort(cities.begin(), cities.end());

    cout << get_max(cities, x, y) << endl;

    return 0;
}