#include <fstream>
#include <unordered_map>
using namespace std;

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

int main()
{
    int n;
    in >> n;

    unordered_map<int,bool> um;

    while(n--)
    {
        int o, x;
        in >> o >> x;

        switch(o)
        {
        case 1:
            um.insert({x,1});
            break;
        case 2:
            um.erase(x);
            break;
        case 3:
            out << (um.find(x) != um.end() ? 1 : 0) << '\n';
            break;
        }
    }

    return 0;
}