fn main() {
	const SZ : usize = 1_000_000;
    input!{
		n: usize, _h: usize,
		ab: [(usize, usize); n],
	}

	// いもす法で区間加算する
	let mut acc = vec![0i64; SZ + 9];
	for (a, b) in ab {
		acc[a] += 1;
		acc[b+1] -= 1;
	}
	for i in 0..=SZ+5 {
		acc[i+1] += acc[i];
	}

	// 最も多い時間帯を答える
	let mut ans = 0;
	for i in 0..=SZ+5 {
		ans = max(ans, acc[i]);
	}
	println!("{}", ans);
}

// const MOD17: usize = 1000000007;
// const MOD93: usize = 998244353;
// const INF: usize = 1 << 60;
// let dx = vec![!0, 0, 1, 0]; // 上左下右
// let dy = vec![0, !0, 0, 1]; // 上左下右
// let d = vec!{(!0, 0), (0, !0), (1, 0), (0, 1)}; // 上左下右

#[allow(unused)]
use proconio::{input, marker::Chars, marker::Usize1};

#[allow(unused)]
use std::{
	mem::swap,
	cmp::min, cmp::max,
	cmp::Reverse,
	collections::HashSet, collections::BTreeSet,
	collections::HashMap, collections::BTreeMap,
	collections::BinaryHeap,
	collections::VecDeque,
	iter::FromIterator,
};