#include <bits/stdc++.h>

using namespace std;

ifstream fin("heapuri.in");
ofstream fout("heapuri.out");

set<int>S;
queue<int>q;
int n;
int a[200005], cnt;
int main()
{
    int x, op;
    fin >> n;
    while(n--)
    {
        fin >> op;
        if(op == 1)
        {
            fin >> x;
            S.insert(x);
            a[++cnt] = x;
        }
        else if(op == 2)
        {
            fin >> x;
            S.erase(a[x]);
        }
        else
        {
            for(auto i : S)
            {
                fout << i << "\n";
                break;
            }
        }
    }
    return 0;
}