#include <iostream>
#include <fstream>
#include <unordered_set>

using namespace std;
ifstream fin ("hashuri.in");
ofstream fout ("hashuri.out");
int n,x,op;
unordered_set <int> a;
int main()
{
    fin>>n;
    for(int i=1;i<=n;i++)
    {
        fin>>op>>x;
        if(op==1)
            a.insert(x);
        if(op==2)
            a.erase(x);
        if(op==3)
        {
            if(a.find(x)==a.end())
                fout<<0<<'\n';
            else
                fout<<1<<'\n';
        }
    }
    return 0;
}