#include <bits/stdc++.h>
using namespace std;
#define letter s[i]-'a'
const int alpha_size = 26;
int op;
string str;

class PrefixTree  {
  public :
           vector <PrefixTree*> son;
           PrefixTree *root;
           int count_words;
           int count_childs;

           PrefixTree(){
             count_words=0;
             count_childs=0;
             son.resize(alpha_size,NULL);
           }

          void pushWord(PrefixTree *node, int i, string s){
            if (!isalpha(s[i])) {
              ++node->count_words;
              return;
            }
            if (!node->son[letter]) {
                    node->son[letter]=new PrefixTree;      // if there is not a son which starts with this letter
                    ++node->count_childs;
                    }
            pushWord(node->son[letter],i+1,s);
          }

          bool popWord(PrefixTree* node,int i,string s){
            if (!isalpha(s[i])) {
              --node->count_words;           // end of the string
              }
             else {
                if (node->popWord(node->son[letter],i+1,s)) {
                        --node->count_childs;
                        node->son[letter]=NULL;
                }
             }
            if (node->count_childs == 0 && node->count_words == 0 && node != root) {
                    delete node;
                    return 1;
                    }
            return 0;
          }

          int getNumberOfWords(PrefixTree* node,int i,string s){
             if (!isalpha(s[i])) return node->count_words;
             if (!node->son[letter]) return 0;
             return getNumberOfWords(node->son[letter],i+1,s);
          }

          int getLengthOfPrefix (PrefixTree* node, int i, string s) {
              if (!isalpha(s[i]) || !node->son[letter] ) return i; // return the length found until now
              return getLengthOfPrefix(node->son[letter],i+1,s); // otherwise go to the child with the next character
           }
   } Trie;

int main() {
    freopen ("trie.in","r",stdin);
    freopen ("trie.out","w",stdout);
    Trie.root = new PrefixTree;
    while (cin>>op>>str) {
        switch(op){
          case  0 : Trie.pushWord(Trie.root,0,str); break;
          case  1 : Trie.popWord(Trie.root,0,str); break;
          case  2 : cout<<Trie.getNumberOfWords(Trie.root,0,str)<<'\n'; break;
          default : cout<<Trie.getLengthOfPrefix(Trie.root,0,str)<<'\n'; break;
           }
    }
    return 0;
}