#include <bits/stdc++.h>

using namespace std;

class Treap {
  
  typedef struct _Node {
  public:
    int key, priority;
    int m_size;
    _Node *l, *r;
    
    _Node(const int x) : key(x), priority(rand() & 1073741823), m_size(1), l(NULL), r(NULL) {
    }

    void update() {
      this->m_size = 1;
      if (l) {
        this->m_size += this->l->m_size;
      }
      if (r) {
        this->m_size += this->r->m_size;
      }
    }
  } *Node;

  Node merge(Node L, Node R) {
    if (!L || !R)
      return L ? L : R;
    
    if (L->priority < R->priority) {
      L->r = merge(L->r, R);
      L->update();
      return L;
    } else {
      R->l = merge(L, R->l);
      R->update();
      return R;
    }
  }

  void split(Node T, const int key, Node &L, Node &R) {
    L = R = NULL;

    if (T) {
      if (T->key < key) {
        split(T->r, key, T->r, R);
        L = T;
      } else {
        split(T->l, key, L, T->l);
        R = T;
      }
      T->update();
    }
  }

  bool find(Node T, const int key) {
    if (!T)
      return 0;
    if (T->key == key)
      return 1;
    if (key < T->key)
      return find(T->l, key);
    else
      return find(T->r, key);
  }

  Node root;

public:

  Treap() : root(NULL) {
    srand(time(0));
  }

  bool find(const int key) {
    return find(root, key);
  }

  void insert(const int key) {
    if (!find(key)) {
      Node L, R;
      split(root, key, L, R);
      root = merge(merge(L, new _Node(key)), R);
    }
  }

  void erase(const int key) {
    if (find(key)) {
      Node L, R, M;
      split(root, key, L, M);
      split(M, key + 1, M, R);
      delete M;
      root = merge(L, R);
    }
  }
} T;

int main() {
  ifstream fin("hashuri.in");
  ofstream fout("hashuri.out");
  fin.tie(0);
  ios_base::sync_with_stdio(false);

  int n; fin >> n;

  for (int i = 0; i < n; ++ i) {
    int opType, key; fin >> opType >> key;
    if (opType == 1)
      T.insert(key);
    else if (opType == 2)
      T.erase(key);
    else
      fout << T.find(key) << '\n';
  }
  fin.close();
  fout.close();
  return 0;
}