#include <bits/stdc++.h>
using namespace std;
int a[100001], b[100001];
int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i] >> b[i];
  sort(a, a + n);
  sort(b, b + n);
  b[n] = -1;
  int ans = 1, top = 0;
  int k = 1;
  for (int i = 0; i < n; i++) {
    k++;
    while (b[top] == k) top++, k--;
    if (a[i] <= k) ans = max(ans, k);
  }
  cout << ans - 1 << endl;
  return 0;
}
