#include <ext/hash_set>
#include <cstdio>

int main()
{
	int t, nr, N;
	__gnu_cxx::hash_set<int> set;
	freopen("hashuri.in", "r", stdin);
	freopen("hashuri.out", "w", stdout);
	scanf("%d\n", &N);
	for (int i = 0; i != N; ++i) {
		scanf("%d %d\n", &t, &nr);
		if (t == 1) set.insert(nr);
		else if (t == 2) set.erase(nr);
		else
			if (set.find(nr) == set.end()) printf("0\n");
			else printf("1\n");
	}
}