#include <cstring>
#include <cstdio>
#include <iostream>
using namespace std;

const int MAXLG = 20;
const int ALPHALEN = 26;

struct node
{
    int wordsCount;
    int prefixCount;
    char currentWord[MAXLG+1];
    char letter;
    node* next[ALPHALEN+1];
};

node* root = NULL;

void initNode(node** x)
{
    *x = new(node);
    (*x)->wordsCount = 0;
    (*x)->prefixCount = 0;
    for(int i = 0; i < ALPHALEN; i++)
        ((*x)->next)[i] = NULL;
}

void addWord(int pos, char* word, node** x)
{
    if(pos == strlen(word))
        return;

    if(*x == NULL)
        initNode(x);

    (*x)->letter = word[pos];

    (*x)->prefixCount++;

    if(pos == strlen(word)-1)
    {
        strcpy((*x)->currentWord,word);
        (*x)->wordsCount++;
    }

    addWord(pos+1,word,&(((*x)->next)[word[pos+1]-'a']));
}

void deleteWord(int pos, char* word, node** x)
{
    (*x)->prefixCount--;

    if(pos == strlen(word) - 1)
        (*x)->wordsCount--;
    else
        deleteWord(pos+1,word,&(((*x)->next)[word[pos+1]-'a']));

    if((*x)->prefixCount == 0 && (*x)->wordsCount == 0 && *x != root)
    {
        delete *x;
        *x = NULL;
    }
}

int getWordCount(int pos, char* word, node** x)
{
    if(*x == NULL)
        return 0;
    else
    if(pos == strlen(word) - 1)
        return (*x)->wordsCount;
    else
        getWordCount(pos+1,word,&(((*x)->next)[word[pos+1]-'a']));
}


void parcurgere(node* x)
{
    if(strlen(x->currentWord) != 0)
        printf("%s %d %d\n",x->currentWord,x->wordsCount,x->prefixCount);

    for(int i = 0; i < ALPHALEN; i++)
        if((x->next)[i] != NULL)
            parcurgere((x->next)[i]);
}

int len = 0;

void getMaxLenPrefix(int pos, char* word, node** x)
{
    if(pos == strlen(word) || (*x) == NULL)
        return;

    if((*x)->prefixCount >= 1)
        len = max(len, pos + 1);

    getMaxLenPrefix(pos+1,word,&(((*x)->next)[word[pos+1]-'a']));
}


int main()
{
    freopen("trie.in","r",stdin);
    freopen("trie.out","w",stdout);

    initNode(&root);

    int type, x;
    char w[MAXLG+1];

    while(scanf("%d",&type) == 1)
    {
        scanf("%s",w);
        switch(type)
        {
            case 0:
                addWord(0,w,&(((root)->next)[w[0]-'a']));
                break;

            case 1:
                deleteWord(0,w,&(((root)->next)[w[0]-'a']));
                break;

            case 2:
                x = getWordCount(0,w,&(((root)->next)[w[0]-'a']));
                printf("%d\n",x);
                break;

            case 3:
                len = 0;
                getMaxLenPrefix(0,w,&(((root)->next)[w[0]-'a']));
                printf("%d\n",len);
                break;
        }
    }

    return 0;
}