#include <iostream>
#include <fstream>
#include <algorithm>
#include<bits/stdc++.h>
#include<vector>
using namespace std;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
long n,i,k,cont,v[10001],w[10001],j,x,m,op;
set<int> h;
int main()
{
    in>>n;
    int l=0;
    while(n)
    {
        in>>op>>x;
        if(op==1)
            h.insert(x);
        if(op==2)
            h.erase(x);
        if(op==3)
            {
                if(h.find(x)!=h.end())
                    out<<1<<'\n';
                else
                    out<<0<<'\n';
            }

        n--;
    }
    return 0;
}