#include <cstdio>
#include <cassert>
#include <algorithm>
#include <vector>
#include <map>
#include <functional>

// for debug
#include <random>
#include <unistd.h>

// for release
#define fprintf(...) void(0)

template <class T>
class RedBlackTree {
  struct Node {
    Node *children[2]={nullptr, nullptr}, *parent=nullptr;
    T value;
    enum Color { RED, BLACK } color=RED;
    Node(T x): value(x) {}
  } *root=nullptr;

  RedBlackTree(Node *root): root(root) {
    if (root) {
      root->parent = nullptr;
      root->color = Node::BLACK;
    }
  }

  bool is_red(Node *node) const {
    return node && node->color == Node::RED;
  }

  size_t black_height() const {
    size_t res=0;
    for (Node *cur=root; cur; cur=cur->children[0])
      if (cur->color == Node::BLACK) ++res;

    return res;
  }

  void rotate(Node *cur, int dir) {
    // dir == 0: left-rotate
    // dir == 1: right-rotate

    Node *child=cur->children[!dir];
    assert(child);
    cur->children[!dir] = child->children[dir];
    if (child->children[dir])
      child->children[dir]->parent = cur;

    child->parent = cur->parent;
    if (cur->parent == nullptr) {
      root = child;
    } else if (cur == cur->parent->children[dir]) {
      cur->parent->children[dir] = child;
    } else {
      cur->parent->children[!dir] = child;
    }
    child->children[dir] = cur;
    cur->parent = child;
  }

  Node *successor(Node *cur) const {
    if (cur->children[1]) {
      cur = cur->children[1];
      while (cur->children[0])
        cur = cur->children[0];

      return cur;
    }

    while (true) {
      if (cur->parent == nullptr) return nullptr;
      if (cur == cur->parent->children[0]) return cur->parent;
      cur = cur->parent;
    }
  }

  void insert_fixup(Node *cur) {
    while (is_red(cur->parent)) {
      Node *gparent=cur->parent->parent;
      assert(gparent);

      int uncle_dir=(cur->parent != gparent->children[1]);
      Node *uncle=gparent->children[uncle_dir];

      if (is_red(uncle)) {
        cur->parent->color = uncle->color = Node::BLACK;
        gparent->color = Node::RED;
        cur = gparent;
        continue;
      }
      if (cur == cur->parent->children[uncle_dir]) {
        cur = cur->parent;
        rotate(cur, !uncle_dir);
      }
      cur->parent->color = Node::BLACK;
      cur->parent->parent->color = Node::RED;
      rotate(gparent, uncle_dir);
    }
    root->color = Node::BLACK;
  }

  void erase_fixup(Node *cur, Node *parent) {
    while (cur != root && !is_red(cur)) {
      int sibling_dir=(cur == parent->children[0]);
      Node *sibling=parent->children[sibling_dir];

      if (is_red(sibling)) {
        sibling->color = Node::BLACK;
        parent->color = Node::RED;
        rotate(parent, !sibling_dir);
        sibling = parent->children[sibling_dir];
      }

      if (sibling) {
        if (!is_red(sibling->children[0]) && !is_red(sibling->children[1])) {
          sibling->color = Node::RED;
          cur = parent;
          parent = cur->parent;
          continue;
        }

        if (!is_red(sibling->children[sibling_dir])) {
          if (sibling->children[!sibling_dir])
            sibling->children[!sibling_dir]->color = Node::BLACK;

          sibling->color = Node::RED;
          rotate(sibling, sibling_dir);
          sibling = parent->children[sibling_dir];
          assert(sibling);
        }

        sibling->color = parent->color;
        sibling->children[sibling_dir]->color = Node::BLACK;
      }

      parent->color = Node::BLACK;
      rotate(parent, !sibling_dir);
      cur = root;
      parent = nullptr;
    }
    if (cur) cur->color = Node::BLACK;
  }

public:
  RedBlackTree() = default;

  const Node *find(T x) const {
    const Node *cur=root;
    while (cur != nullptr) {
      if (cur->value == x) break;
      cur = cur->children[cur->value < x];
    }
    if (cur == nullptr) return nullptr;

    return cur;
  }

  bool contains(T x) const {
    return find(x) != nullptr;
  }

  std::pair<Node *, bool> insert(T x) {
    if (root == nullptr) {
      root = new Node(x);
      root->color = Node::BLACK;
      return {root, true};
    }

    Node **child=&root, *parent=nullptr;
    while (*child) {
      parent = *child;
      if ((*child)->value == x) return {*child, false};
      child = &(*child)->children[(*child)->value < x];
    }
    *child = new Node(x);
    (*child)->parent = parent;
    insert_fixup(*child);
    return {*child, true};
  }

  Node *erase(T x) {
    Node *cur=root;
    while (cur != nullptr) {
      if (cur->value == x) break;
      cur = cur->children[cur->value < x];
    }
    if (cur == nullptr) return nullptr;

    // Note: erased node should not be delete'd, but be just detached
    return erase(cur);
  }

  Node *erase(Node *cur) {
    if (cur == nullptr) return nullptr;

    Node *y=cur;
    if (cur->children[0] && cur->children[1]) y = successor(y);
    assert(y != nullptr);

    Node *x=y->children[0];
    if (x == nullptr) x = y->children[1];

    if (x) x->parent = y->parent;
    if (y->parent == nullptr) {
      root = x;
    } else {
      y->parent->children[y == y->parent->children[1]] = x;
    }
    Node *xparent=y->parent;  // not x->parent; in case x is null
    bool fix_needed=(y->color == Node::BLACK);
    if (y != cur) {
      // keep detached node intact; not use cur->value = y->value.
      y->parent = cur->parent;
      y->children[0] = cur->children[0];
      y->children[1] = cur->children[1];
      y->color = cur->color;

      if (y->children[0]) y->children[0]->parent = y;
      if (y->children[1]) y->children[1]->parent = y;
      if (y->parent) {
        y->parent->children[cur == cur->parent->children[1]] = y;
      } else {
        root = y;
      }

      if (xparent == cur) {
        xparent = y;
        if (x) x->parent = xparent;
      }
    }

    if (fix_needed)
      erase_fixup(x, xparent);

    cur->children[0] = cur->children[1] = cur->parent = nullptr;
    return cur;
  }

  bool verify() const {
    if (root == nullptr) return true;

    auto report=[](const char *s) {
      fprintf(stderr, "%sviolated:%s %s%s%s\n",
              "\x1b[31;1m", "\x1b[0m",
              "\x1b[37;1m", s, "\x1b[0m");
    };

    bool violated=false;
    if (root->color == Node::RED) {
      violated = true;
      report("root node is red");
    }

    bool reached=false;
    size_t bheight=-1;
    std::function<void (Node *, int, size_t)> dfs=[&](
        Node *subroot, int depth, size_t bh) {

      if (subroot->color == Node::RED) {
        // Note: once violated, we continue checking.  We may not assume
        //       the root node is black.
        if (subroot->parent && subroot->parent->color == Node::RED) {
          violated = true;
          report("two consecutive nodes are red");
        }
      } else {
        ++bh;
      }

      Node *left=subroot->children[0], *right=subroot->children[1];

      if (!(left && right)) {
        if (!reached) {
          bheight = bh;
          reached = true;
        } else if (bheight != bh) {
          violated = true;
          report("different number of black nodes in two root-leaf paths");
        }
      }

      if (right) dfs(right, depth+1, bh);

      fprintf(stderr, "%s%*s%d%s (%zu)%s\n",
              is_red(subroot)? "\x1b[31;1m":"\x1b[37;1m",
              depth*2+2, "  ", subroot->value, "\x1b[0m", bh,
              (left && right)? "":" *");

      if (left) dfs(left, depth+1, bh);
    };

    fprintf(stderr, "================================================\n");
    dfs(root, 0, 0);
    fprintf(stderr, "================================================\n");
    return !violated;
  }
};

int main() {
  RedBlackTree<int> rbt;
  size_t size=0;

  int q;
  scanf("%d", &q);

  for (int i=0; i<q; ++i) {
    int t, x;
    scanf("%d %d", &t, &x);
    if (t == 0) {
      if (rbt.insert(x).second) ++size;
      printf("%zu\n", size);
    } else if (t == 1) {
      printf("%d\n", rbt.contains(x));
    } else if (t == 2) {
      if (rbt.contains(x)) --size;
      rbt.erase(x);
    }
  }
  assert(rbt.verify());
}



Measured memory_bytes: 12032