#include <stdio.h>
#include <map>

using namespace std;

int n,nr;
map <int,int> m;

int main()
{
 freopen("hashuri.in", "r", stdin);
 freopen("hashuri.out", "w", stdout);

 int i,tip,x;

 scanf("%d ",&n);

 for(i=1;i<=N;i++) 
 {
  scanf("%d %d ",&tip,&x);

  if (tip == 1 && M.find(x)==M.end())
   M[x] = ++NR;

  if (tip == 2)
   M.erase(x);

  if (tip == 3) 
   printf("%d\n", M.find(x) != M.end());
 }

 return 0;
}