#include <cstdio>
#include <set>

using namespace std;

#define FIN "hashuri.in"
#define FOUT "hashuri.out"

int n,tip,x;
set <int> v;

int main()
{
	freopen(FIN,"r",stdin);
	freopen(FOUT,"w",stdout);
	
	scanf("%d", &n);
	for (int i=1;i<=n;++i)
	{
		scanf("%d %d", &tip,&x);
		if (tip==1)
			v.insert(x);
		else
		if (tip==2)
            v.erase(x);
		else
 		if (v.find(x)==v.end()) printf("0\n");
                            else printf("1\n");
	}
	
	fclose(stdin);
	fclose(stdout);
	
	return 0;
}