#include <cstdio>
#include <tr1/unordered_set>

using namespace std;

typedef std::tr1::unordered_set<int> myHash;

int main() {
  freopen("hashuri.in", "r", stdin);
  freopen("hashuri.out", "w", stdout);

  int n;
  scanf("%d", &n);
  myHash M;
  while (n--) {
    int op, x;
    scanf("%d %d", &op, &x);
    if (op == 1) {
      M.insert(x);
      continue;
    }
    if (op == 2) {
      M.erase(x);
      continue;
    }
    if (M.find(x)!=M.end()) printf("1\n");
    else printf("0\n");
  }

  return 0;
}