#include <fstream>
#include <set>
using namespace std;

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

int n,i,op,x;
set<int> v;

int main(){
    fin>>n;
    for (i=1;i<=n;i++){
        fin>>op>>x;
        if (op==1)
            v.insert(x);
        if (op==2)
            v.erase(x);
        if (op==3){
            if (v.find(x)!=v.end())
                fout<<"1\n";
            else
                fout<<"0\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}