#include <fstream>
#include <cstring>
#pragma GCC optimize("O3")
#pragma GCC optimize("fast-math")
#pragma GCC optimize("unroll-loops")
const int NMAX=25;

using namespace std;
ifstream fin("trie.in");
ofstream fout("trie.out");

struct node
{
    int cnt, nrc;
    node* v[26];

    node()
    {
        cnt=nrc=0;
        for(int i=0; i<26; i++) v[i]=NULL;
    }
};
typedef node* trie;

void inserare(trie, char*, int);
bool stergere(trie, char*, int);
int nr_ap(trie, char*, int);
int lp(trie, char*, int, int);
bool ok(trie);

trie root;
char s[NMAX];
int tip;

int main()
{
    root=new node;
    while(fin>>tip>>s)
    {
        if(tip==0) inserare(root, s, strlen(s));
        if(tip==1) stergere(root, s, strlen(s));
        if(tip==2) fout<<nr_ap(root, s, strlen(s))<<'\n';
        if(tip==3) fout<<lp(root, s, strlen(s), 0)<<'\n';
    }
    return 0;
}

void inserare(trie nod, char* s, int lg)
{
    if(lg==0)
    {
        nod->cnt++;
        return;
    }
    if(nod->v[s[0]-'a']==NULL)
    {
        nod->v[s[0]-'a']=new node;
        nod->nrc++;
    }
    inserare(nod->v[s[0]-'a'], (s+1), lg-1);
}

bool stergere(trie nod, char* s, int lg)
{
    if(lg==0)
    {
        nod->cnt--;
        return ok(nod);
    }
    if(stergere(nod->v[s[0]-'a'], (s+1), lg-1))
    {
        delete nod->v[s[0]-'a'];
        nod->v[s[0]-'a']=NULL;
        nod->nrc--;
        return ok(nod);
    }
    return false;
}

int nr_ap(trie nod, char* s, int lg)
{
    if(lg==0) return nod->cnt;
    if(nod->v[s[0]-'a']) return nr_ap(nod->v[s[0]-'a'], (s+1), lg-1);
    return 0;
}

int lp(trie nod, char* s, int lg, int lvl)
{
    if(lg==0) return lvl;
    if(nod->v[s[0]-'a']) return max(lvl+1, lp(nod->v[s[0]-'a'], (s+1), lg-1, lvl+1));
    return 0;
}

bool ok(trie nod)
{
    return (!nod->cnt && !nod->nrc);
}