#include <iostream>
#include <cstdio>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <cstring>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <cmath>
#include <cassert>
#include <set>
#include <complex>
#include <bitset>
#include <sstream>
#include <iomanip>
#include <numeric>
#include <climits>
#include <string>

using namespace std;

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

#define mp make_pair
#define fi first
#define se second
#define pb push_back
#define endl '\n'
#define eps 1e-8
#define io  ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);
#define file freopen ("in.txt", "r", stdin),freopen ("out.txt", "w", stdout);
#define filein freopen ("in.txt", "r", stdin);
#define all(v) ((v).begin()), ((v).end())
#define mid ((st + en) >> 1)

const int N = 2e5 + 5;


ll dp[N];

int n, x, y;

struct node{
	int x, y, h, c;
	bool operator <(const node &that) const{
		return h < that.h;
	}
} a[N];

ll f(int idx){
	ll &ret = dp[idx];
	if(ret != -1)
		return ret;
	ret = a[idx].c;
	for(int i = idx + 1; i < n; i++)
		if(a[i].h > a[idx].h && abs(a[i].x - a[idx].x) <= x &&
			 abs(a[i].y - a[idx].y) <= y
			 )
		ret = max(ret, f(i) + a[idx].c);
	return ret;
}

int main(){
	//filein;
	cin >> n >> x >> y;
	for(int i = 0; i < n; i++)
		cin >> a[i].x >> a[i].y >> a[i].h >> a[i].c;
	sort(a, a + n);
	memset(dp, -1, sizeof dp);
	long long ret = -(1LL << 60);
	for(int i = 0; i < n; i++)
		ret = max(ret, f(i));
	cout << ret << endl;
	return 0;
}