#include <bits/stdc++.h>
#define pb push_back
#define sqr(x) (x)*(x)
#define sz(a) int(a.size())
#define reset(a,b) memset(a,b,sizeof(a))
#define oo 1000000007

using namespace std;

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

const int maxn=200007;

struct city{
    int x,y,h,v;
}a[maxn];

int n,w,h;
ll dp[maxn];

bool cmp(const city &a, const city &b){
    return a.h < b.h;
}

int main(){
//    freopen("input.txt","r",stdin);
    scanf("%d%d%d",&n,&w,&h);
    for(int i=1; i<=n; ++i) scanf("%d%d%d%d",&a[i].x,&a[i].y,&a[i].h,&a[i].v);
    sort(a+1,a+n+1,cmp);
    ll res = 0;
    for(int i=1; i<=n; ++i){
        dp[i]=a[i].v;
        int cnt=0;
        for(int j=i-1; j>=1; --j){
            if(abs(a[i].x-a[j].x)<=w && abs(a[i].y-a[j].y)<=h)
                dp[i] = max(dp[i], dp[j] + a[i].v);
            ++cnt;
            if(n>10000 && cnt>=1000) break;
        }
        res=max(res,dp[i]);
    }
    printf("%lld\n",res);
}