#include<hash_set.h>
#include<cstdio>
using namespace std;
using namespace __gnu_cxx;
hash_set< int, hash<int> > hs;
int main() {
	int op, v, n;
	freopen("hashuri.in", "r", stdin);
	freopen("hashuri.out", "w", stdout);
	scanf("%d", &n);
	for(; n; --n) {
		scanf("%d%d", &op, &v);
		if(op == 1) hs.insert(v);
		if(op == 2) hs.erase(v);
		if(op == 3) printf("%d\n", hs.find(v) != hs.end());
	}
	return 0;
}