#include <fstream>
#include <set>
using namespace std;
ifstream cin("hashuri.in");
ofstream cout("hashuri.out");
set<int>s;
int n;
int a,x;
int main()
{
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>a>>x;
        if(a==1)
            s.insert(x);
        if(a==2)
            s.erase(x);
        if(a==3)
        {
            set<int>::iterator it;
            it=s.find(x);
            if(it==s.end())
                cout<<"0\n";
            else
                cout<<"1\n";
        }
    }
    return 0;
}
/**
**/