#include<iostream>
#include<fstream>
#include<vector>
#define rest x%mod
#define mod 666013
using namespace std;
vector <int> H[mod];

int find(int x) {
    for(int i=0; i<H[rest].size(); i++)
        if(H[rest][i] == x) return i;
    return -1;
}
void insert(int x) 
{ if(find(x) == -1)
      H[rest].push_back(x); 
 }
   
void del(int x) 
     {
    int poz = find(x);
    if(poz == -1) return;
    swap(H[rest][poz], H[rest][ H[rest].size()-1 ]);
    H[rest].pop_back();
    }   
    
int main()
{ int c,x,i,n;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
 f>>n;
    for(i=1;i<=n;++i)
    {
        f>>c>>x;
        switch(c)
        {
            case 1:insert(x); break;
            case 2:del(x); break;
            case 3:g<<find(x)<<endl; break;
        }
    }
f.close();
g.close();
return 0;}