#include <iostream>
#include <fstream>
#include <set>
using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");

int main()
{
    int N;
    set <int> multime;
    f >> N;
    while(N--) {
        int nrOperatie, x;
        f >> nrOperatie >> x;
        if(nrOperatie == 1 && multime.find(x) == multime.end()) {
            multime.insert(x);
        } else if (nrOperatie == 2 && multime.find(x) != multime.end()) {
            multime.erase(x);
        } else if (nrOperatie == 3) {
            if(multime.find(x) != multime.end())
                g << 1 << endl;
            else g << 0 << endl;
        }
    }
    return 0;
}