#include <iostream>
#include <fstream>
#include <map>
#define NMAX 1000001

using namespace std;

map<int,int> a;
int n,p,x;

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

int main()
{
    in >> n;
    for(int i=0;i<n;i++)
    {
        in >> p >> x;
        if(p==1)
        {
            if(a.find(x) == a.end())
            {
                a[x] = 1;
            }
        } else if(p==2)
        {
            a.erase(x);

        }else
        {
            if(a.find(x)!=a.end())
            {
                out <<1 << "\n";
            }
            else out << 0 << "\n";
        }
    }
    return 0;
}