#include <bits/stdc++.h>
using namespace std;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
unordered_set<int> s;
unordered_set<int>::iterator it;
int main()
{
    int tst,tip,x;
    in>>tst;
    for(int i=1;i<=tst;++i)
    {
        in>>tip>>x;
        if(tip==1) s.insert(x);
        else if(tip==2)
        {
            it=s.find(x);
            if(it!=s.end()) s.erase(it);
        }
        else out<<(s.find(x)!=s.end())<<'\n';
    }
    return 0;
}