#include <stdio.h>
#include <fstream>
#include <iostream>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <cstring>

#define ch (*s - 'a')

using namespace std;

struct trie {
    int word;
    int prefix;
    trie *edge[30];
   trie () {   word = prefix = 0;
    memset(edge , 0 , sizeof(edge));}
};

trie *T = new trie;

void addword(trie *nod, char *s)
{
    if (*s == '\n') {nod->word += 1; return;}

    if (nod->edge[ch ] == 0 )
    {
        nod ->edge[ch] = new trie;
        nod->prefix++;
    }
   addword(nod->edge[ch],s+1);
}

int delword(trie *nod, char *s)
{
    if (*s == '\n') nod->word -=1;
      else
    if (delword(nod->edge[ch],s+1))
    {
        nod->edge[ch] = 0;
        nod->prefix--;
    }
    if (nod->word == 0 && nod->prefix == 0 && nod != T)
    {        delete nod; return 1;   }
    return 0;
}

int nword(trie *nod,char *s)
{
    if (*s == '\n') { return nod->word; }

    if (nod->edge[ch] )
       return nword(nod->edge[ch],s+1);
    return 0;
}

int npref(trie *nod,char *s, int k)
{
    if ((*s == '\n' )|| (nod->edge[ch] == 0))
          return k;
    return npref(nod->edge[ch],s+1,k+1);
}

int main()
{
    freopen("trie.in", "r", stdin);
    freopen("trie.out" , "w", stdout);

        char s[ 32 ];
fgets (s, 32 , stdin);
    while ( !feof(stdin) )
    {
        switch ( s[0] )
         {
         case '0' : addword(T,s+2); break;
         case '1' : delword(T,s+2); break;
         case '2' : printf("%d\n",nword(T,s+2) ); break;
         case '3' : printf("%d\n",npref(T,s+2,0)); break;
         }
         fgets (s, 32 , stdin);
    }

    return 0;
}