//package Awesome;



import java.awt.Point;
import java.io.*;
 
import java.util.*;
 
 
 
 
 
 
 
 
 
 class TestClass {
 
static long mod ;


public static class Batman{
	
	  int lat;
	  int lon;
	  int heigh;
	  int score;
	public Batman(int lat, int lon, int heigh, int score) {
	
		this.lat = lat;
		this.lon = lon;
		this.heigh = heigh;
		this.score = score;
	}
	  
}
 
 
public static void main(String args[] ) throws java.lang.Exception {
 
 
 
InputStream inputStream = System.in;
InputReader in = new InputReader(inputStream);
 
//BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
//BufferedReader in = new BufferedReader(new FileReader("C:\\Users\\sompatha\\Desktop\\yes.txt"));
//Scanner in = new Scanner(new FileReader("C:\\Users\\Sompathak\\Desktop\\yes.txt"));
 //PrintWriter pw = new PrintWriter(new FileWriter("C:\\Users\\sompatha\\Desktop\\output.txt"));
//InputStream inputStream = System.in;
//InputReader in = new InputReader(inputStream);
//Scanner in = new Scanner(new InputStreamReader(System.in));
//Scanner in = new Scanner(new FileReader("C:\\Users\\sompatha\\Desktop\\yes.txt"));
//we can we will ??? !!!!!! SOM RISES
//long startTime = System.currentTimeMillis();
//long startTime = System.currentTimeMillis();
 
//float endTime   = System.currentTimeMillis();
//float totalTime = (endTime - startTime)/(float)1000;
//System.out.println(totalTime+" sec....."); 
//System.out.println(check(2,2)+" "+check_2(2,2));

int n = in.nextInt();
int x = in.nextInt();
int y = in.nextInt();
Batman[] Q = new Batman[n];

for(int i=0;i<n;i++) Q[i] = new Batman(in.nextInt(),in.nextInt(),in.nextInt(), in.nextInt());
Arrays.sort(Q,new Comparator<Batman>() {

	@Override
	public int compare(Batman a, Batman b) {
		// TODO Auto-generated method stub
		return a.heigh-b.heigh;
	}
});
long[] dp = new long[n];
dp[0]=Q[0].score;
long max=dp[0];
for(int i=1;i<n;i++){
    dp[i]=Q[i].score;
    if(n<9000){
	for(int j=0;j<i;j++){
		
		 if(Math.abs(Q[i].lat-Q[j].lat)<=x && Math.abs(Q[i].lon-Q[j].lon)<=y){
			 
			     dp[i] = Math.max(dp[i],dp[j]+Q[i].score);
		 }
    }
    if(max<dp[i]) max=dp[i];
    } else max+=dp[i];
}
System.out.println(max);

 
}public static class InputReader
{
private InputStream stream;
private byte[] buf = new byte[1024];
private int curChar;
private int numChars;
private SpaceCharFilter filter;
 
public InputReader(InputStream stream)
{
this.stream = stream;
}
 
public int read()
{
if (numChars == -1)
throw new InputMismatchException();
if (curChar >= numChars)
{
curChar = 0;
try
{
numChars = stream.read(buf);
} catch (IOException e)
{
throw new InputMismatchException();
}
if (numChars <= 0)
return -1;
}
return buf[curChar++];
}
 
public int nextInt()
{
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-')
{
sgn = -1;
c = read();
}
int res = 0;
do
{
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
} while (!isSpaceChar(c));
return res * sgn;
}
 
public String readString()
{
int c = read();
while (isSpaceChar(c))
c = read();
StringBuilder res = new StringBuilder();
do
{
res.appendCodePoint(c);
c = read();
} while (!isSpaceChar(c));
return res.toString();
}
public double readDouble() {
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
double res = 0;
while (!isSpaceChar(c) && c != '.') {
if (c == 'e' || c == 'E')
return res * Math.pow(10, nextInt());
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
}
if (c == '.') {
c = read();
double m = 1;
while (!isSpaceChar(c)) {
if (c == 'e' || c == 'E')
return res * Math.pow(10, nextInt());
if (c < '0' || c > '9')
throw new InputMismatchException();
m /= 10;
res += (c - '0') * m;
c = read();
}
}
return res * sgn;
}
public long readLong() {
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
long res = 0;
do {
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
} while (!isSpaceChar(c));
return res * sgn;
}
public boolean isSpaceChar(int c)
{
if (filter != null)
return filter.isSpaceChar(c);
return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
}
 
public String next()
{
return readString();
}
 
public interface SpaceCharFilter
{
public boolean isSpaceChar(int ch);
}
}
}