#include <bits/stdc++.h>
using namespace std;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

set<int> multime;
int main()
{
    int choice, n;
    int element;
    set<int>::iterator it;
    fin >> n;
    for (int i = 0; i < n; i++)
    {
        fin >> choice;
        switch (choice)
        {
        case 1:
            fin >> element;
            multime.insert(element);
            break;
        case 2:
            fin >> element;
            it = multime.find(element);
            if (it != multime.end())
                multime.erase(it);
            break;
        case 3:
            fin >> element;
            it = multime.find(element);
            if (it != multime.end())
            {
                fout << 1 << endl;
            }
            else
            {
                fout << 0 << endl;
            }

            break;
        default:
            break;
        }
    }
    return 0;
}