#include <iostream>
#include <cstdio>
#include <set>
using namespace std;
int op,N,val;
set <int> H;
int main()
{
    freopen("hashuri.in","r",stdin);
    freopen("hashuri.out","w",stdout);
    cin>>N;
    for(int i=1;i<=N;i++)
    {
        cin>>op>>val;
        if(op==1)
            H.insert(val);
        else if(op==2)
            H.erase(val);
        else
        {
            if(H.find(val)==H.end())
                cout<<"0\n";
            else
                cout<<"1\n";
        }
    }
    return 0;
}