#include <bits/stdc++.h>

using namespace std;

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

int N;
set<int> H;

int main()
{
    fin>>N;
    while(N--)
    {
        int op,x;
        fin>>op>>x;
        if(op==1)
            H.insert(x);
        if(op==2)
            H.erase(x);
        if(op==3)
           H.find(x)!=H.end() ? fout<<"1\n" : fout<<"0\n";
    }

    return 0;
}