package no165;

import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int b = sc.nextInt();
		Point[] p = new Point[n];
		for(int i=0;i<n;i++) {
			p[i] = new Point(sc.nextInt(),sc.nextInt(),sc.nextInt(),i);
		}
		Arrays.sort(p, (x,y) -> Integer.compare(x.x, y.x));
		for(int i=1;i<n;i++) {
			p[i].xr = p[i-1].xr + ((p[i].x == p[i-1].x) ? 0 : 1);
		}
		int w = p[n-1].xr + 1;
		Arrays.sort(p, (x,y) -> Integer.compare(x.y, y.y));
		for(int i=1;i<n;i++) {
			p[i].yr = p[i-1].yr + ((p[i].y == p[i-1].y) ? 0 : 1);
		}
		int h = p[n-1].yr + 1;
		int[][] count = new int[h+1][w+1];
		int[][] point = new int[h+1][w+1];
		for(int i=0;i<n;i++) {
//			System.out.println(p[i].xr + "," + p[i].yr);
			count[p[i].yr + 1][p[i].xr + 1]++;
			point[p[i].yr + 1][p[i].xr + 1] += p[i].p;
		}
//		System.out.println(Arrays.deepToString(point));
		for(int i=1;i<=h;i++) {
			for(int j=0;j<=w;j++) {
				point[i][j] += point[i-1][j];
				count[i][j] += count[i-1][j];
			}
		}
//		System.out.println(Arrays.deepToString(point));

//		for(int i=0;i<=h;i++) {
//			for(int j=1;j<w;j++) {
//				point[i][j] += point[i][j-1];
//				count[i][j] += count[i][j-1];
//			}
//		}
		int ans = 0;
		for(int i1=1;i1<=h;i1++) {
			for(int i2=i1;i2<=h;i2++) {
				int sump = 0;
				int sumc = 0;
				int j2 = 1;
				for(int j1=1;j1<=w;j1++) {
					while(j2 <= w && sump + point[i2][j2] - point[i1-1][j2] <= b) {
						sump += point[i2][j2] - point[i1-1][j2];
						sumc += count[i2][j2] - count[i1-1][j2];
						j2++;
					}
					ans = Math.max(ans, sumc);
					sump -= point[i2][j1] - point[i1-1][j1];
					sumc -= count[i2][j1] - count[i1-1][j1];
				}
			}
		}
		System.out.println(ans);
	}


	static class Point {
		int x,y,p,xr,yr,i;
		public Point(int x,int y,int p,int i) {
			this.x = x;
			this.y = y;
			this.p = p;
			this.i = i;
		}
	}

}