/* Bismillahir Rahmanir Rahim */

#include <bits/stdc++.h>

#define rep(i, n)	for(int i=0;i<int(n);i++)
#define repn(i, n)	for(int i=1;i<=int(n);i++)
#define set(i, n)	memset(i, n, sizeof(i))

#define pb	push_back
#define f	first
#define s	second

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int N = 100007;

int n, x, y;
long long X[N], Y[N], Z[N], P[N];
long long dp[N];
int vis[N];
int order[N];

long long recur(int at){
	if(vis[at]) return dp[at];
	vis[at] = 1;
	long long ret = 0;
	for(int j=at+1;j<=n;j++){
        int i = order[j];
		if(abs(X[i] - X[order[at]]) <= x && abs(Y[i] - Y[order[at]]) <= y && Z[i] > Z[order[at]]) ret = max(ret, recur(j));
	}
	return dp[at] = ret + P[order[at]];
}


bool comp(int a, int b){
    return Z[a] < Z[b];
}

int main(){
	scanf("%d %d %d", &n, &x, &y);
	repn(i, n) scanf("%lld %lld %lld %lld", &X[i], &Y[i], &Z[i], &P[i]);
	repn(i, n) order[i] = i;
    sort(order+1, order+1+n, comp);
    long long ret = 0;
	repn(i, n) ret = max(ret, recur(i));
	cout << ret << endl;
	return 0;
}