#include<fstream>
#define NMAX 21
using namespace std;
struct trie
{
    int na;
    int nf;
    trie *fiu[26];
    trie()
    {
        na = nf = 0;
        for(int i = 0; i < 26; i++)
        {
            fiu[i] = 0;
        }
    }
};
trie *rad;
int cerinta;
char _char[NMAX];
ifstream _cin("trie.in");
ofstream _cout("trie.out");
void _insert(trie *nod, char *_char)
{
    if(*_char == 0)
    {
        nod -> na++;
        return;
    }
    if(nod -> fiu[*_char - 'a'] == NULL)
    {
        nod -> fiu[*_char - 'a'] = new trie;
        nod -> nf++;
    }
    _insert(nod -> fiu[*_char - 'a'], _char + 1);
}
int aparitii(trie *nod, char *_char)
{
    if(*_char == 0)
    {
        return nod -> na;
    }
    if(nod -> fiu[*_char - 'a'] == NULL)
    {
        return 0;
    }
    return aparitii(nod -> fiu[*_char - 'a'], _char + 1);
}
int prefix(trie *nod, char *_char)
{
    if(*_char == 0)
    {
        return 0;
    }
    if(nod -> fiu[*_char - 'a'] == NULL)
    {
        return 0;
    }
    return 1 + prefix(nod -> fiu[*_char - 'a'], _char + 1);
}
bool sterge(trie *nod, char *_char)
{
    if(*_char == 0)
    {
        nod -> na--;
        if(nod -> na == 0 && nod -> nf == 0 && nod != rad)
        {
            delete nod;
            return 1;
        }
    }
    if(nod -> fiu[*_char - 'a'] == NULL)
    {
        return 0;
    }
    if(!sterge(nod -> fiu[*_char - 'a'], _char + 1))
    {
        return 0;
    }
    nod -> fiu[*_char - 'a'] = NULL;
    nod -> nf--;
    if(nod -> na == 0 && nod -> nf == 0 && nod != rad)
    {
        delete nod;
        return 1;
    }
    return 0;
}

int main()
{
    rad = new trie;
    while(_cin >> cerinta)
    {
        _cin >> _char;
        if(cerinta == 0)
        {
            _insert(rad, _char);
            continue;
        }
        if(cerinta == 1)
        {
            sterge(rad, _char);
            continue;
        }
        if(cerinta == 2)
        {
            _cout << aparitii(rad, _char) << "\n";
            continue;
        }
        _cout << prefix(rad, _char) << "\n";
    }
    return 0;
}