#include<fstream>
#include<set>
using namespace std;
int nrop, op, x;
set<int> s;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
int main(){
    in>>nrop;
    for(;nrop--;){
        in>>op>>x;
        if(op==1)
            s.insert(x);
        if(op==2)
            s.erase(x);
        if(op==3){
            if(s.find(x)!=s.end())
                out<<"1"<<"\n";
            else
                out<<"0"<<"\n";
        }
    }
return 0;
}