import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Comparator;
import java.util.InputMismatchException;
import java.util.NoSuchElementException;

public class Main {

	static PrintWriter out;
	static InputReader ir;
	static final int INF=Integer.MAX_VALUE;

	static void solve() {
		int n=ir.nextInt();
		int c=ir.nextInt();
		int[][] a=new int[n][];
		int[] imos=new int[(int)1e5+2];
		for(int i=0;i<n;i++)
			a[i]=ir.nextIntArray(3);
		Arrays.sort(a,new Comparator<int[]>(){
			public int compare(int[] a,int[] b){
				if(a[2]!=b[2])
					return a[2]-b[2];
				else
					return a[0]-b[0];
			}
		});
		for(int i=0;i<n;i++){
			int begin=a[i][0];
			while(i<n-1){
				if(a[i][2]==a[i+1][2]&&a[i][1]==a[i+1][0])
					i++;
				else break;
			}
			int end=a[i][1];
			imos[begin]++;
			imos[end+1]--;
		}
		int ma=0;
		for(int i=0;i<=(int)1e5;i++){
			imos[i+1]+=imos[i];
			ma=Math.max(ma,imos[i+1]);
		}
		out.println(ma);
	}

	static int col(char c){
		if(c=='R')
			return 0;
		if(c=='G')
			return 1;
		return 2;
	}

	static String convert(String s){
		for(int i=0;i<s.length()-1;i++){
			if(s.charAt(i)==s.charAt(i+1))
				return convert(s.substring(0, i)+(i==s.length()-2?"":s.substring(i+2)));
		}
		return s;
	}

	public static void main(String[] args) throws Exception {
		ir = new InputReader(System.in);
		out = new PrintWriter(System.out);
		solve();
		out.flush();
	}

	static class InputReader {

		private InputStream in;
		private byte[] buffer = new byte[1024];
		private int curbuf;
		private int lenbuf;

		public InputReader(InputStream in) {
			this.in = in;
			this.curbuf = this.lenbuf = 0;
		}

		public boolean hasNextByte() {
			if (curbuf >= lenbuf) {
				curbuf = 0;
				try {
					lenbuf = in.read(buffer);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (lenbuf <= 0)
					return false;
			}
			return true;
		}

		private int readByte() {
			if (hasNextByte())
				return buffer[curbuf++];
			else
				return -1;
		}

		private boolean isSpaceChar(int c) {
			return !(c >= 33 && c <= 126);
		}

		private void skip() {
			while (hasNextByte() && isSpaceChar(buffer[curbuf]))
				curbuf++;
		}

		public boolean hasNext() {
			skip();
			return hasNextByte();
		}

		public String next() {
			if (!hasNext())
				throw new NoSuchElementException();
			StringBuilder sb = new StringBuilder();
			int b = readByte();
			while (!isSpaceChar(b)) {
				sb.appendCodePoint(b);
				b = readByte();
			}
			return sb.toString();
		}

		public int nextInt() {
			if (!hasNext())
				throw new NoSuchElementException();
			int c = readByte();
			while (isSpaceChar(c))
				c = readByte();
			boolean minus = false;
			if (c == '-') {
				minus = true;
				c = readByte();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res = res * 10 + c - '0';
				c = readByte();
			} while (!isSpaceChar(c));
			return (minus) ? -res : res;
		}

		public long nextLong() {
			if (!hasNext())
				throw new NoSuchElementException();
			int c = readByte();
			while (isSpaceChar(c))
				c = readByte();
			boolean minus = false;
			if (c == '-') {
				minus = true;
				c = readByte();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res = res * 10 + c - '0';
				c = readByte();
			} while (!isSpaceChar(c));
			return (minus) ? -res : res;
		}

		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public int[] nextIntArray(int n) {
			int[] a = new int[n];
			for (int i = 0; i < n; i++)
				a[i] = nextInt();
			return a;
		}

		public long[] nextLongArray(int n) {
			long[] a = new long[n];
			for (int i = 0; i < n; i++)
				a[i] = nextLong();
			return a;
		}

		public char[][] nextCharMap(int n, int m) {
			char[][] map = new char[n][m];
			for (int i = 0; i < n; i++)
				map[i] = next().toCharArray();
			return map;
		}
	}
}

Measured memory_bytes: 29312