#include <fstream>
#include <set>
#define ind first
#define val second
using namespace std;

ifstream f("hashuri.in");
ofstream g("hashuri.out");
set<int> s;
int n, k, i, v;
long long sol;
int main()
{
    f>>n;
    for(i=1; i<=n; i++)
    {
        f>>k>>v;
        if(k==1)
            s.insert(v);
        else if(k==2)
            s.erase(v);
        else
            if(s.find(v)==s.end())
                g<<"0\n";
            else
                g<<"1\n";
    }

    return 0;
}