#include <fstream>
#include <map>

using namespace std;

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

int n,t,i,x;
map <int,int >a;

int main()
{

    f>>n;

    for (i=1;i<=n;i++)
     {
         f>>t>>x;
         if (t==1 && a.find(x)==a.end())
           a[x]=1;
         if (t==2 && a.find(x)!=a.end())
           a.erase(x);
          if (t==3)
           g<<(a.find(x)!=a.end())<<'\n';
     }
  f.close();
  g.close();
}