#include<fstream>
#include<unordered_set>

std::ifstream fin("hashuri.in");
std::ofstream fout("hashuri.out");

std::unordered_set<int> S;
int n, task, x;

int main(){
    fin >> n;
    while(n--){
        fin >> task >> x;
        if(task == 1){
            S.insert(x);
        }
        else if(task == 2){
            S.erase(x);
        }
        else if(task == 3){
            if(S.find(x) == S.end())
                fout << "0\n";
            else
                fout << "1\n";
        }
    }
}