#include<bits/stdc++.h>
using namespace std;
struct score
{
int a;
int b;
int c;
int d;	
};
struct score s[200010];

bool comp(struct score x,struct score y)
{
	return x.c-y.c;
}

int c[100010],n,x,y,i,j;
int main()
{
cin>>n>>x>>y;
for(i=0;i<n;i++)
cin>>s[i].a>>s[i].b>>s[i].c>>s[i].d;	
sort(s,s+n,&comp);
memset(c,0,sizeof c);
c[0]=s[0].d;
for(i=1;i<n;i++)
{
	for(j=0;j<i;j++)
	{
		if(abs(s[i].a-s[j].a)<=x && abs(s[i].b-s[j].b)<=y && c[i] < c[j]+s[i].d)
		c[i]=c[j]+s[i].d;
	}
}
cout<<c[n-1]<<endl;
}