#include <map>

using namespace std;

map <int, int> M;
int N,NR,x,y;

int main()
{
	freopen("hashuri.in","r",stdin);
	freopen("hashuri.out","w",stdout);
	scanf("%d", &N);
	for (int i=1;i<=N;i++)
	{
		scanf("%d %d", &x, &y);
		if (x==1 && M.find(y)==M.end()) M[y]=++NR;
		if (x==2) M.erase(y);
		if (x==3) printf("%d\n", M.find(y) != M.end());
	}
	return 0;
}