#include <fstream>
#include <cstring>
#define ch (*s-'a')

using namespace std;

struct Trie
{
    int nrfii,fr;
    Trie *leg[26];
    Trie()
    {
        nrfii=fr=0;
        memset(leg,0,sizeof(leg));
    }
};
Trie *rad=new Trie;

inline void Add(Trie *nod, char *s)
{
    if(*s=='\0')
    {
        nod->fr++;
        return;
    }
    if(nod->leg[ch]==0)
    {
        nod->leg[ch]= new Trie;
        nod->nrfii++;
    }
    Add(nod->leg[ch],s+1);
}

inline int Delete(Trie *nod, char *s)
{
    if(*s=='\0')
        nod->fr--;
    else
        if(Delete(nod->leg[ch],s+1))
        {
            nod->nrfii--;
            nod->leg[ch]=0;
        }
    if(nod->fr==0 && nod->nrfii==0 && nod!=rad)
    {
        delete nod;
        return 1;
    }
    return 0;
}

inline int Query(Trie *nod, char *s)
{
    if(*s=='\0')
        return nod->fr;
    if(nod->leg[ch]==0)
        return 0;
    return Query(nod->leg[ch],s+1);
}

inline int LgPrefix(Trie *nod, char *s, int l)
{
    if(*s=='\0' || nod->leg[ch]==0)
        return l;
    return LgPrefix(nod->leg[ch],s+1,l+1);
}

int main()
{
    int tip;
    char s[30];
    ifstream fin ("trie.in");
    ofstream fout ("trie.out");
    while(fin>>tip>>s)
    {
        if(!tip)
            Add(rad,s);
        else
            if(tip==1)
                Delete(rad,s);
            else
                if(tip==2)
                    fout<<Query(rad,s)<<"\n";
                else
                    fout<<LgPrefix(rad,s,0)<<"\n";
    }
    fin.close();
    fout.close();
    return 0;
}