# include <cstdio>
# include <ext/hash_map>
using namespace std;
using namespace __gnu_cxx ;

const char *FIN = "hashuri.in", *FOU = "hashuri.out" ;

int N;
hash_map <int, int> M;

int main (void) {
    freopen (FIN, "r", stdin) ;
    freopen (FOU, "w", stdout) ;

    scanf ("%d ", &N) ;
    for (int i = 1, op, x, cnt = 0; i <= N; ++i) {
        scanf ("%d %d ", &op, &x) ;
        if (op == 1 && M.count (x) == 0) M[x] = ++cnt;
        else if (op == 2) M.erase (x);
        else if (op == 3) printf ("%d\n", M.count (x) > 0) ;
    }
}