#include<stdio.h>
#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<string.h>
using namespace std;

typedef long long LL;
typedef vector<int> VI;

#define REP(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define EACH(i,c) for(__typeof((c).begin()) i=(c).begin(),i##_end=(c).end();i!=i##_end;++i)
#define eprintf(...) fprintf(stderr, __VA_ARGS__)

template<class T> inline void amin(T &x, const T &y) { if (y<x) x=y; }
template<class T> inline void amax(T &x, const T &y) { if (x<y) x=y; }
template<class Iter> void rprintf(const char *fmt, Iter begin, Iter end) {
    for (bool sp=0; begin!=end; ++begin) { if (sp) putchar(' '); else sp = true; printf(fmt, *begin); }
    putchar('\n');
}

int N, X, Y;
const int MAXN = 200111;
struct Data {
    int a, b, h, s;
    bool operator<(const Data &y) const {
	return h < y.h;
    }
} D[MAXN];
LL dp[MAXN];

int main() {
    scanf("%d%d%d", &N, &X, &Y);
    REP (i, N) scanf("%d%d%d%d", &D[i].a, &D[i].b, &D[i].h, &D[i].s);
    sort(D, D+N);

    REP (i, N) {
	const Data &d = D[i];
	dp[i] = d.s;
	REP (j, i) if (d.h > D[j].h && abs(d.a - D[j].a) <= X && abs(d.b - D[j].b) <= Y)
	    amax(dp[i], dp[j] + d.s);
    }

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