#include <fstream>
#include <unordered_set>

using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
unordered_set<int> S;
int n,o,v;
int main()
{
    f>>n;
    for(;n;n--)
    {
        f>>o>>v;
        if(o==1)
            S.insert(v);
        else
            if(o==2)
                S.erase(v);
        else
            if(S.find(v)==S.end())
                g<<"0\n";
            else
                g<<"1\n";
    }
    return 0;
}