#include<fstream>
#include<cstring>
#include<vector>
using namespace std;

ifstream f("trie.in");
ofstream g("trie.out");

int lg,size=1;
char sir[25];

struct nod {
    int v[30],wd,pfx;
    void init ()
    {
        wd=0, pfx=0;
        memset(v,0,sizeof(v));
    }
} blank;
vector<nod> T;

void add (int nod, int crt)
{
    T[nod].pfx++;
    if (crt==lg)
        T[nod].wd++;
    else
    {
        int& next_nod=T[nod].v[sir[crt]-'a'];
        if (!next_nod)
            next_nod=size, T.push_back(blank), size++;
        add(next_nod,crt+1);
    }
}

void erase (int nod, int crt)
{
    T[nod].pfx--;
    if (crt==lg)
        T[nod].wd--;
    else
        erase(T[nod].v[sir[crt]-'a'],crt+1);
}

int query_words (int nod, int crt)
{
    if (crt==lg)
        return T[nod].wd;
    else
    {
        int next_nod=T[nod].v[sir[crt]-'a'];
        if (!next_nod)
            return 0;
        return query_words(next_nod,crt+1);
    }
}

int query_lcp (int nod, int crt)
{
    if (crt==lg)
        return crt;
    else
    {
        int next_nod=T[nod].v[sir[crt]-'a'];
        if (!next_nod || !T[next_nod].pfx)
            return crt;
        return query_lcp(next_nod,crt+1);
    }
}

int main ()
{
    int tip;
    T.push_back(blank);
    T.push_back(blank);
    f>>tip;
    f.get();
    f.get(sir,25);
    while (!f.eof())
    {
        lg=strlen(sir);
        if (tip==0)
            add(1,0);
        if (tip==1)
            erase(1,0);
        if (tip==2)
            g<<query_words(1,0)<<"\n";
        if (tip==3)
            g<<query_lcp(1,0)<<"\n";
        f>>tip;
        f.get();
        f.get(sir,25);
    }
    return 0;
}