#include<bits/stdc++.h>
using namespace std;

int n,a,b;
int A[100002]={},B[100002]={};

int main()
{
  cin>>n;
  for(int i=0;i<n;i++){
    cin>>a>>b;
    A[a]++;
    B[b+1]++;
  }
  int sum=1,ans=0;
  for(int i=1;i<100002;i++){
    sum+=(A[i]-B[i]);
    //if(i<=10)cout<<i<<" "<<sum<<endl;
    if(i<=sum)ans=i;
  }
  cout<<ans-1<<endl;
  return 0;
}