#include <unordered_map>
#include <iostream>
#include <fstream>

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

int N, NR;
std::unordered_map <int, int> M;

int main()
{
    int i, tip, x;
    
    f>>N;
    
    for (i = 1; i <= N; i++)
    {
        f>>tip>>x;
        
        if (tip == 1 && M.find(x)==M.end()) M[x] = ++NR;
        if (tip == 2) M.erase(x);
        if (tip == 3) g<< (M.find(x) != M.end())<<std::endl;
    }
    
    return 0;
}