#include <iostream>
#include <fstream>
#include <map>

using namespace std;

map<int,int> m;

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

int main()
{
    int n,t,x,nr=1;
    fin>>n;
    for(int i=1;i<=n;i++)
    {
        fin>>t>>x;
        if(t==1 && m.find(x)==m.end())m[x]=nr++;
        if(t==2)m.erase(x);
        if(t==3) fout<<(m.find(x)!=m.end())<<'\n';
    }
}