#include <bits/stdc++.h>
using namespace std;
int n, m, ans = 0, a[200005], ll, rr;
struct node {
  int l, r;
  bool operator<(const node &b) const { return l > b.l; }
} b[200005];
priority_queue<int, vector<int>, greater<int> > q;
int main() {
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    cin >> b[i].l >> b[i].r;
  }
  sort(b + 1, b + n + 1);
  ll = 1, rr = m;
  for (int i = 1; i <= n; i++) {
    q.push(b[i].r);
    if (ll <= rr && ll <= b[i].l) {
      ll = ll + 1;
    } else {
      a[++a[0]] = q.top();
      q.pop();
    }
  }
  sort(a + 1, a + a[0] + 1);
  for (int i = a[0]; i >= 1; i--) {
    if (ll <= rr && a[i] <= rr) {
      rr--;
    } else
      ans++;
  }
  cout << ans;
}
