#include <bits/stdc++.h>

using namespace std;
struct city
{
  int la,lo,h,p;  
};
bool compareHeight(city c1, city c2)
{
    return (c1.h < c2.h);
}
int main(){
    int n,x,y,i,j;
    long long int sum1=0,sum2=0,max;
    cin >> n >> x >> y;
        city * c = new city[n];
    for(i= 0; i < n; i++)
    {
        cin >> c[i].la >> c[i].lo >> c[i].h >> c[i].p;    
    }
    sort(c,c+n,compareHeight);
    sum1=sum2=max=c[0].p;
    for(i=0;i<n;i++)
    { 
      sum2=sum1;
      sum1=c[i].p; 
      for(j=i+1;j<n;j++)
       {
         if((int)abs(c[i].la-c[j].la)<=x &&  (int)abs(c[i].lo-c[j].lo)<=y)
         { 
             sum1+=c[j].p;
              i=j;
         }  
       }
      if(sum1>=sum2)
          max=sum1;
      else
         max=sum2;        
    } 
    printf("%lld",max);
    return 0;
}