#include <bits/stdc++.h>
#define ASCIIMAX 30
#define int long long int
#define double long double
#define cin fin
#define cout fout

using namespace std;

ifstream fin("trie.in");
ofstream fout("trie.out");
class Trie
{
  const int NMAX;
  Trie** sons;
  int cate;
  static int TestValidity(Trie* tmp)
  {
      bool ok=0;
      int i;
      for(i=0;i<tmp->NMAX;i++)
          if( tmp->sons[i])
             {ok=1;break;}
     return ok;
  }
public:
    Trie():NMAX(ASCIIMAX), cate(0)
    {
        sons= new Trie*[NMAX];
        int i;
        for(i=0;i<NMAX;i++)
            sons[i]=NULL;
    }
    friend void AddAparition(Trie * tmp,const char* p)
    {
        if(*(p)==NULL)
        {   
            tmp->cate++;
        }
        else
        {
            if( tmp->sons[ p[0]-'a'  ]==0)
                tmp->sons[p[0]-'a']= new Trie;
            AddAparition(tmp->sons[p[0]-'a'],p+1);
            
        }
    }
    friend int HowMany( Trie* tmp, const char* p)
    {
        if(*(p)==NULL)
        {
            return tmp->cate;
        }
        else
        {
            if(  tmp->sons[ p[0]-'a'  ]==0)
              return 0;
            return  HowMany(tmp->sons[p[0]-'a'],p+1);
             
        }
    }

    friend int DecAparition(Trie* tmp,const  char* p)
    {
        if(*(p)==NULL)
        {
            if( tmp->cate!=0)
            tmp->cate--;
            ///analizam daca acest nod are rost sa existe sau nu
            return TestValidity(tmp);


        }
        else
        {
            if( tmp->sons[ p[0]-'a'  ]!=0)
            {

              int value=DecAparition(tmp->sons[ p[0]-'a'  ], p+1);
              if( !value)
                  {
                  delete tmp->sons[ p[0]-'a'  ];
                  tmp->sons[ p[0]-'a'  ]=NULL;
                  }  
            }
            
               return TestValidity(tmp);    
        }
    }
    friend int LongestPrefix(Trie* tmp, const char* p)
    {
        if( *(p)==NULL)
           return 0;
        if(   tmp->sons[p[0]-'a']  )
            {
                return 1+ LongestPrefix(tmp-> sons[p[0]-'a'],p+1);
            }
            else
            return 0;
    }
};
int32_t main()
{
    const int MAX_LENGTH=25;
    Trie* root=new Trie;
    int cer;
    char string_to_add[MAX_LENGTH];
    while(cin>>cer)
    {
        cin>>string_to_add;
        switch (cer)
        {
        case 0:
            AddAparition(root,string_to_add);
            break;
        case 1:
            DecAparition(root, string_to_add);
            break;
        case 2:
            cout<<HowMany(root, string_to_add)<<'\n';
            break;
            
        default:
            cout<<LongestPrefix(root, string_to_add)<<'\n';
            break;
        }
    }
return 0;
}