#include <fstream>
#include <unordered_set>

using namespace std;

//const int nmax=1000000;

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

unordered_set <int> s;

int main(){
    int n;
    fin>>n;
    for(int i=1;i<=n;i++){
        int x,y;
        fin>>x>>y;
        if(x==1){
            s.insert(y);
        }else if(x==2){
            s.erase(y);
        }else{
            if(s.find(y)==s.end()){
                fout<<"0\n";
            }else{
                fout<<"1\n";
            }
        }
    }
    return 0;
}