#include<bits/stdc++.h>
//#include <set>
using namespace std;
ifstream f("heapuri.in");
ofstream g("heapuri.out");
int m,k;
set <int>s;
int ord[200005];
int main()
{
    f>>m;
    for(;m;m--)
    {
        int t,a;
        f>>t;
        if(t==3)
            g<<(s.begin())<<"\n";
        else
        {
            f>>a;
            if(t==1)
                s.insert(a), ord[++k] = a;
            else
                s.erase(ord[a]);
    }
  }
  return 0;
}