#include <fstream>
#include <cstring>
using namespace std;
ofstream fout("trie.out");
ifstream fin("trie.in");

class Trie {
private:
    Trie * next[26];
    int contor;

    int max(int a, int b){
        return a >= b ? a : b;
    }

public:
    Trie(){
        contor = 0;
        memset(next, 0, sizeof(next));
    }

    void _insert(char* word) {
        Trie *pos= this;
        while(*word != 0){
            if (pos->next[*word - 'a'] == NULL) {
                pos->next[*word - 'a'] = new Trie();
            }

            pos = pos->next[*word - 'a'];
            word++;
        }

        pos->contor++;
    }

    int _count(char* word) {
        Trie *pos= this;
        while(*word != 0){
            if (pos->next[*word - 'a'] == NULL) {
                return 0;
            }

            pos = pos->next[*word - 'a'];
            word++;
        }

        return pos->contor;
    }

    bool _erase(char* word) {
        if (*word == 0) {
            if (this->contor == 0) {
                return false;
            }

            else {
                this->contor--;
                return (this->contor ==0);
            }
        }

        if (this->next[*word - 'a'] == NULL) {
            return false;
        }

        bool aux = this->next[*word - 'a']->_erase(word + 1);

        if (aux) {
            Trie* son = this->next[*word - 'a'];
            bool toDelete = (son->contor == 0);
            if (toDelete)
                for (int i = 0; i < 26; i++) {
                    toDelete &= (son->next[i] == NULL);
                }

            if (toDelete) {
                delete son;
                this->next[*word - 'a'] = NULL;
            }
        }

        return aux;
    }

    int lgPrefix(char* word, int lg) {
        if (*word == NULL) {
            return lg;

        }

        if (this->next[*word - 'a'] == NULL) {
            return lg;
        }

        return this->next[*word - 'a']->lgPrefix(word + 1, lg + 1);
    }
};

Trie *trie = new Trie();
char word[25];

int main()
{
    int o;

    while (fin >> o >> word) {
        switch (o) {
        case 0: trie->_insert(word); break;
        case 1: trie->_erase(word); break;
        case 2: fout << trie->_count(word) << '\n'; break;
        case 3: fout << trie->lgPrefix(word, 0) << '\n'; break;
        }
    }
    return 0;
}