#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n,count=0; 
    int cx,i; 
    int cy; 
    scanf("%d %d %d",&n,&cx,&cy);
    int x[n]; 
        int y[n]; 
        int z[n]; 
        int points[n]; 
        
    for(int i = 0; i< n; i++){
        scanf("%d %d %d %d",&x[i],&y[i],&z[i],&points[i]);
        
        // your code goes here
    }
    int temp;
    for(i=0;i<n;i++){
        for(int j=i;j<n;j++){
            if(x[i]>x[i+1]){
                temp = x[i];
                x[i] = x[i+1];
                x[i+1]=temp;
                temp = y[i];
                y[i] = y[i+1];
                y[i+1]=temp;
                temp = z[i];
                z[i] = z[i+1];
                z[i+1]=temp;
                temp = points[i];
                points[i] = points[i+1];
                points[i+1]=temp;
            }
    }
    }
    int t1,t2,t3;
    for(i=0;i<n-1;i++){
        t1 =x[i+1]-x[i];
        if(t1<=cx){
            count+=points[i];
        }        
    }
    count+=points[i+1];
    printf("%d ",count);
    return 0;
}