#include <bits/stdc++.h>
#define LL long long
#define FOR(i,c) for(__typeof(c.begin()) i = c.begin(); i != c.end(); i++)
#define F first
#define S second
using namespace std;

const LL mod = 1e9 + 7;

template<typename T> T gcd(T a, T b) { return b == 0?a: gcd(b, a % b); }
template<typename T> T LCM(T a, T b) { return a*(b/gcd(a, b)); }
template<typename T, typename S> T expo(T b, S e, const T &m){if(e <= 1)return e == 0?1: b;\
	return (e&1) == 0?expo((b*b)%m, e>>1, m): (b*expo((b*b)%m, e>>1, m))%m;}
template<typename T, typename S> T expo(T b, S e){if(e <= 1)return e == 0?1: b;\
	return (e&1) == 0?expo((b*b), e>>1): (b*expo((b*b), e>>1));}
template<typename T, typename S> T modinv(T a, S mod) { return expo(a, mod-2, mod); }
template<class T, class S> std::ostream& operator<<(std::ostream &os, const std::pair<T, S> &t) {
	os<<"("<<t.first<<", "<<t.second<<")";
	return os;
}
template<class T> std::ostream& operator<<(std::ostream &os, const std::vector<T> &t) {
	os<<"["; FOR(it,t) { if(it != t.begin()) os<<", "; os<<*it; } os<<"]";
	return os;
}
#define gc getchar_unlocked
template <typename T> void in(T &x) {
	T c = gc(); while(((c < 48) || (c > 57)) && (c!='-')) c = gc();
	bool neg = false; if(c == '-') neg = true; x = 0; for(;c < 48 || c > 57;c=gc());
	for(;c > 47 && c < 58;c=gc())	x = (x*10) + (c - 48); if(neg)	x = -x;
}


const int MAXN = 2e5 + 3;

int n, x, y;

struct city {
  int a, b, h;
  LL val;
  int idx;
  bool operator<(const city &other) const {
    return h < other.h;
  }
} data[MAXN];

LL dp[MAXN];
LL res = 0;

int main() {
  in(n), in(x), in(y);
  for(int i = 0; i < n; i++) {
    in(data[i].a), in(data[i].b), in(data[i].h), in(data[i].val);
    data[i].idx = i;
  }
  sort(data, data + n);
  for(int i = 0; i < n; i++) {
    dp[i] = data[i].val;
    for(int j = i - 1; j >= 0; j--) {
      if(abs(data[i].a - data[j].a) <= x and abs(data[i].b - data[j].b) <= y
          and data[i].h > data[j].h) {
        dp[i] = max(dp[i], dp[j] + data[i].val);
      }
    }
    res = max(res, dp[i]);
  }
  printf("%lld\n", res);
  return 0;
}