#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, imos[100003] = {0};
  imos[0] = 1;
  cin >> n;
  for (int i = 0; i < n; i++) {
    int a, b;
    cin >> a >> b;
    imos[a]++, imos[b + 1]--;
  }
  for (int i = 1; i < 100003; i++) {
    imos[i] += imos[i - 1];
  }
  int maxi = 0;
  for (int i = 0; i <= n; i++) {
    if (imos[i] >= i) maxi = max(maxi, i);
  }
  cout << maxi - 1 << endl;
}
