#include <fstream>
#include <string>

using namespace std;

struct nod{
    nod *fi[26];
    bool isL;
    int wordCount;
    
    nod()
    {
        isL = false;
        wordCount = 0;
        for(int i = 0 ; i < 26 ; i++)
            fi[i] = nullptr;
    }
};

void ins(nod *r, const string& key)
{
    nod *curr = r;
    for(char c : key)
    {
        if(curr->fi[c - 'a'] == nullptr)
        {
            nod *newNod = new nod();
            curr->fi[c - 'a'] = newNod;
        }
        curr = curr->fi[c - 'a'];
    }
    curr->isL = true;
    curr->wordCount++;
}

bool search(nod *r, const string& key)
{
    nod *curr = r;
    for(char c : key)
    {
        if(curr->fi[c - 'a'] == nullptr)
            return false;
        curr = curr->fi[c - 'a'];
    }
    return curr->isL;
}

bool isEmpty(nod *r)
{
    for(int i = 0 ; i < 26 ; i++)
        if(r->fi[i])
            return false;
    return true;
}

nod *del(nod *r, string key, int depth = 0)
{
    if(!r)
        return NULL;
    if(depth == key.size())
    {
        if(r->isL)
        {
            r->wordCount--;
            if(r->wordCount == 0)
                r->isL = false;
        }
        if(isEmpty(r))
        {
            delete r;
            r = NULL;
        }
        return r;
    }
    
    int ind = key[depth] - 'a';
    r->fi[ind] = del(r->fi[ind], key, depth + 1);
    
    if(isEmpty(r) && r->isL == false)
    {
        delete r;
        r = NULL;
    }
    return r;
}

int count(nod *r, const string& key)
{
    nod *curr = r;
    for(auto c : key)
    {
        if(curr->fi[c - 'a'] == nullptr)
            return 0;
        curr = curr->fi[c - 'a'];
    }
    return curr->isL ? curr->wordCount : 0;
}

int longestCommonPrefixLength(nod *r, const string& w)
{
    nod *curr = r;
    int length = 0;
    
    for(char c : w)
    {
        int index = c - 'a';
        if(curr->fi[index] == nullptr)
            break;
        curr = curr->fi[index];
        length++;
    }
    
    return length;
}

int main()
{
    ifstream fin("trie.in");
    ofstream fout("trie.out");
    
    nod *r = new nod();
    
    int op;
    string word;
    
    while(fin >> op >> word)
    {
        if(op == 0)
            ins(r, word);
        if(op == 1)
            del(r, word);
        if(op == 2)
            fout << count(r, word) << '\n';
        if(op == 3)
            fout << longestCommonPrefixLength(r, word) << '\n';
    }

    return 0;
}