#include <bits/stdc++.h>
#include <ext/hash_set>
using namespace std;
using namespace __gnu_cxx;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
int x;
hash_set <int> H;
int main()
{
	for(in >> x; x > 0; x--)
	{
		int i, nr;
		in >> i >> nr;
		if(i == 1) H.insert(nr);
		if(i == 2) H.erase(nr);
		if(i == 3) out << (H.find(nr) != H.end()) << "\n";
	}
    in.close();
    out.close();
    return 0;
}