#include <iostream>
#include <fstream>
#include <map>
using namespace std;

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

int n, nr;
map <int, int> m;

int main()
{
    f >> n;
    int x, op;
    for(int i = 1; i <= n; ++i) {
        f >> op >> x;
        if(op == 1 && m.find(x) == m.end())
            m[x] = ++nr;
        else if(op == 2)
                m.erase(x);
        else g << ((m.find(x) != m.end()) ? "1\n" : "0\n");
    }
}