#include <bits/stdc++.h>

struct Trie {
   std::shared_ptr<Trie[]> children{nullptr};
   int count = 0;
   bool partial_word{false};

   void insert(const std::string &s, int index = 0) {
         if (index == s.size()) {
            count++;
         } else {
            int pos = s[index] - 'a';
            if (children == nullptr) {
               children = std::shared_ptr<Trie []>(new Trie[26]);
            }
            children[pos].insert(s, index + 1);
         }
         partial_word = true;
   }

   int find(const std::string &s, int index = 0) {
      if (index == s.size()) {
         return count;
      }
      int pos = s[index] - 'a';

      if (children[pos].partial_word == false) {
         return 0;
      }
      return children[pos].find(s, index + 1);
   }

   void erase(const std::string &s, int index = 0) {
      if (index == s.size()) {
         if (count > 0) {
            count--;
         }

         if (count == 0) {
            partial_word = false;
         }
      }
      int pos = s[index] - 'a';
      if (children) {
         children[pos].erase(s, index + 1);
      }
   }

   int get_longest_prefix(const std::string &s, int index = 0) {
      if (index == s.size()) {
         return 1;
      }

      int pos = s[index] - 'a';
      if (children && children[pos].partial_word == true) {
         return 1 + children[pos].get_longest_prefix(s, index + 1);
      }

      return 0;
   }

   ~Trie() {
      if (children) {

      }
   }


};

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

   std::string line;
   Trie* t = new Trie;

   while (std::getline(in, line)) {
      std::stringstream ss(line);

      int code;
      std::string word;
      ss >> code;
      ss >> word;

      if (code == 0) {
         t->insert(word);
      } else if (code == 1) {
         t->erase(word);
      } else if (code == 2) {
         out << t->find(word) << "\n";
      } else if (code == 3) {
        out << t->get_longest_prefix(word) << "\n";
      }    
   }

   in.close();
   out.close();
   delete t;
   return 0;
}