#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;
}