#include <iostream>
#include <fstream>
#include <cstring>

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

struct nod
{
    int value, fin;
    nod *next[26];

    nod()
    {
        value = fin = 0;
        for (int i =0; i<26; i++)
            next[i] = 0;
    }
} *root = new nod();

void add(string s)
{
    nod *crt = root;

    for(int i=0; i<s.size(); i++)
    {
        int nxt = s[i] - 'a';
        if (crt ->next[nxt] == 0)
            crt ->next[nxt] = new nod();
        crt = crt ->next[nxt];
        ++crt -> value;
    }
    ++ crt-> fin;

}

void remove(nod *root, char *s)
{
    nod *lst = root;
    int nxt = *s - 'a';

    if (*s == '\0')
    {
       --lst -> fin;
       return;
    }

    nod *crt = lst -> next[nxt];
    remove(crt, s + 1);
    --crt -> value;
    if (crt -> value == 0)
    {
        delete crt;
        lst -> next[nxt] = 0;
    }
}

int occurs(string s)
{
    nod *crt = root;

    for(int i=0; i<s.size(); i++)
    {
        int nxt = s[i] - 'a';
        if (crt -> next[nxt] == 0)
            return 0;
        crt = crt -> next[nxt];
    }
    return crt -> fin;
}
int prefix(string s)
{
    nod *crt = root;

    for(int i=0; i<s.size(); i++)
    {
        int nxt = s[i] - 'a';
        if (crt -> next[nxt] == 0)
            return i;
        crt = crt -> next[nxt];
    }
    return s.size();
}

int main()
{
    int act;
    char s[30];

    while (f >> act >> s)
    {
        if (act == 0) add(s);
        else
        if (act == 1) remove(root, s);
        else
        if (act == 2) g << occurs(s) << '\n';
        else
        if (act == 3) g << prefix(s) << '\n';
    }

    f.close();
    g.close();
    return 0;
}