import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int b = sc.nextInt();
        TreeMap<Integer, Integer> compX = new TreeMap<>();
        TreeMap<Integer, Integer> compY = new TreeMap<>();
        Point[] points = new Point[n];
        for (int i = 0; i < n; i++) {
            points[i] = new Point(sc.nextInt(), sc.nextInt(), sc.nextInt());
            compX.put(points[i].x, null);
            compY.put(points[i].y, null);
        }
        int xx = 1;
        for (int x : compX.keySet()) {
            compX.put(x, xx);
            xx++;
        }
        int yy = 1;
        for (int x : compY.keySet()) {
            compY.put(x, yy);
            yy++;
        }
        int[][] scores = new int[xx][yy];
        int[][] counts = new int[xx][yy];
        for (Point p : points) {
            scores[compX.get(p.x)][compY.get(p.y)] += p.value;
            counts[compX.get(p.x)][compY.get(p.y)] ++;
        }
        for (int i = 1; i < xx; i++) {
            for (int j = 1; j < yy; j++) {
                scores[i][j] +=  scores[i - 1][j] + scores[i][j - 1] - scores[i - 1][j - 1];
                counts[i][j] +=  counts[i - 1][j] + counts[i][j - 1] - counts[i - 1][j - 1];
            }
        }
        int max = 0;
        for (int i = 1; i < xx; i++) {
            for (int j = i; j < xx; j++) {
                int right = 1;
                for (int k = 1; k < yy; k++) {
                    while (right < yy && scores[j][right] - scores[j][k - 1] - scores[i - 1][right] + scores[i - 1][k - 1] <= b) {
                        max = Math.max(max, counts[j][right] - counts[j][k - 1] - counts[i - 1][right] + counts[i - 1][k - 1]);
                        right++;
                    }
                }
            }
        }
        System.out.println(max);
    }
    
    static class Point {
        int x;
        int y;
        int value;
        
        public Point(int x, int y, int value) {
            this.x = x;
            this.y = y;
            this.value = value;
        }
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public String next() throws Exception {
        if (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}