# include <iostream>
using namespace std;
const int maxn=200005;
typedef long long int ll;
ll dp[maxn],lat[maxn],lon[maxn],h[maxn],p[maxn];
int main()
{
    int n,x,y;
    cin>>n>>x>>y;
    for(int i=0;i<n;i++)
        cin>>lat[i]>>lon[i]>>h[i]>>p[i];
    ll res=0;
    for(int i=0;i<n;i++)
    {
        ll z=0;
        for(int j=0;j<i;j++)
        {
            if(h[j]<h[i] and abs(lat[i]-lat[j])<=x and abs(lon[i]-lon[j])<=y)
                z=max(z,dp[j]);
        }
        dp[i]=z+p[i];
        res=max(res,dp[i]);
    }
    cout<<res;
    return 0;
}