#include<bits/stdc++.h>
using namespace std;
const int MAXN = 2e5+5;
const int MOD = 1e9+7;
const int INF = 2e9;
struct city{
    int latitude, langitude;
    int height;
    int points;
} arr[MAXN];

long long dp[MAXN];

bool cmp(city A, city B){
    return (A.height < B.height);
}

int main(){
    int N = 0, diff_x = 0, diff_y = 0;
    scanf("%i%i%i",&N,&diff_x,&diff_y);

    for(int i=1;i<=N;i++)
        scanf("%i%i%i%i",&arr[i].latitude,&arr[i].langitude,&arr[i].height,&arr[i].points);

    sort(arr+1,arr+N+1,cmp);

    for(int i=1;i<=N;i++)
        dp[i] = arr[i].points;

    for(int i=1;i<=N;i++)
        for(int j=1;j<i;j++)
            if( abs(arr[i].latitude - arr[j].latitude <= diff_x) )
                if( abs(arr[i].langitude - arr[j].langitude) <= diff_y)
                    dp[i] = max(dp[i], dp[j] + arr[i].points);

    printf("%lld",*max_element(dp + 1,dp + N + 1));
    return 0;
}