#include<fstream>
#include<unordered_map>
using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
int n,x,t,i;
unordered_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;
        else
            if(t==2&&a.find(x)!=a.end())
               a.erase(x);
            else
                if(t==3)
                   g<<(a.find(x)!=a.end())<<'\n';
      }
    f.close();g.close();
    return 0;
}