#include <cstdio>
#include <unordered_set>
 
using namespace std;
 
int main()
{
  freopen("hashuri.in", "r", stdin);
  freopen("hashuri.out", "w", stdout);
 
  int N, op, x;
  unordered_set<int> hash;
 
  scanf("%d", &N);
  for (int i = 0; i < N; ++i) {
    scanf("%d%d", &op, &x);
    if (op == 1) {
      hash.insert(x);
      continue;
    }
    if (op == 2) {
      hash.erase(x);
      continue;
    }
    printf("%d\n", hash.count(x) == 1);
  }
  
  return 0;
}