#include <bits/stdc++.h>
using namespace std;
#define int long long
int n = 0, m = 0, p = 0, q = 0, tot = 0;
pair<int, int> peo[200500], mid[200500];
bool used[200500];
signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);
	cin >> n >> m;
	for(int i = 1; i <= n; i++) {
		cin >> peo[i].first >> peo[i].second;
		peo[i].second = m + 1 - peo[i].second;
	}
	sort(peo + 1, peo + n + 1);
	for(int i = 1; i <= n; i++)
		if(peo[i].first > p) p++, used[i] = true;
	for(int i = 1; i <= n; i++)
		if(not used[i]) tot++, mid[tot] = peo[i], swap(mid[tot].first, mid[tot].second);
	sort(mid + 1, mid + tot + 1);
	for(int i = 1; i <= tot; i++)
		if(mid[i].first > q) q++;
	cout << n - min(m, p + q) << endl;
	return 0;
}