#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
vector<pair<ll,pair<ll,pair<ll,ll> > > >v;
vector<ll>vv;
int main()
{
    ll i,j,k,l,n,m=0;
    ll a,b,c,d;
    cin>>n>>l>>k;
    for(i=0;i<n;i++)
    {

        cin>>a>>b>>c>>d;
        v.push_back(make_pair(c,make_pair(a,make_pair(b,d))));
    }
    sort(v.begin(),v.end());
    for(i=0;i<n-1;i++)
    {
        if(abs(v[i+1].second.first-v[i].second.first)<=l&&abs(v[i+1].second.second.first-v[i].second.second.first)<=k)
        {
            m+=v[i].second.second.second;
            //cout<<m<<endl;
        }
        else
        {

            vv.push_back(m);
            m=0;
        }
        //cout<<m<<endl;
    }
    if(abs(v[n-1].second.first-v[n-2].second.first)<=l&&abs(v[n-1].second.second.first-v[n-2].second.second.first)<=k)
        {
            m+=v[i].second.second.second;
            vv.push_back(m);
        }

    //cout<<m<<endl;
    ll zz=-900009;
    for(i=0;i<vv.size();i++)
        {

            if(vv[i]>zz)
                zz=vv[i];
        }
        cout<<zz;
    return 0;
}