#include <fstream>
#include <string>

const int SIGMA = 26;

class Trie
{
private:

  int numWords;
  int numChildren;

  Trie* father;
  Trie* children[SIGMA];

public:

  Trie(Trie* father = nullptr)
  {
    this->numWords = 0;
    this->numChildren = 0;

    this->father = father;

    for (int i = 0; i < SIGMA; i++)
      this->children[i] = nullptr;
  }

  void add(std::string word, int pos)
  {
    if (pos >= word.size())
    {
      this->numWords++;
      return;
    }

    if (this->children[word[pos] - 'a'] == nullptr)
    {
      this->children[word[pos] - 'a'] = new Trie(this);
      this->numChildren++;
    }

    this->children[word[pos] - 'a']->add(word, pos + 1);
  }

  void remove(std::string word, int pos)
  {
    if (pos >= word.size())
      this->numWords--;
    else
      this->children[word[pos] - 'a']->remove(word, pos + 1);

    if (pos > 0 && this->numWords == 0 && this->numChildren == 0)
    {
      this->father->numChildren--;
      this->father->children[word[pos - 1] - 'a'] = nullptr;
      delete this;
    }
  }

  int count(std::string word, int pos)
  {
    if (pos >= word.size())
    {
      return this->numWords;
    }

    if (this->children[word[pos] - 'a'] == nullptr)
      return 0;

    return this->children[word[pos] - 'a']->count(word, pos + 1);
  }

  int prefix(std::string word, int pos)
  {
    if(pos >= word.size())
    {
      return word.size();
    }

    if (this->children[word[pos] - 'a'] == nullptr)
      return pos;

    return this->children[word[pos] - 'a']->prefix(word, pos + 1);
  }
};

int main()
{
  std::ifstream in("trie.in");
  std::ofstream out("trie.out");

  Trie* trie = new Trie();

  int type;
  std::string w;

  while (in >> type >> w)
  {
    if (type == 0)
      trie->add(w, 0);
    else if (type == 1)
      trie->remove(w, 0);
    else if (type == 2)
      out << trie->count(w, 0) << '\n';
    else
      out << trie->prefix(w, 0) << '\n';
  }

  return 0;
}