#include <iostream>
#include <fstream>
#include <cassert>

using namespace std;

inline int toInt(char x)
{
    return x - 'a';
}

class Trie
{
public:
    Trie()
    {
        cnt = 0;
        nrChildren = 0;
        for(int i = 0; i < 26; ++i)
            child[i] = nullptr;
    }
    void Insert(char *s)
    {
        if(s[0] == '\0')
        {
            ++cnt;
            return;
        }
        int c = toInt(s[0]);
        if(child[c] == nullptr)
        {
            nrChildren++;
            child[c] = new Trie();
        }
        child[c]->Insert(s + 1);
    }
    bool Delete(char *s)
    {
        if(s[0] == '\0')
        {
            --cnt;
            if(cnt == 0 && nrChildren == 0)
                return true;
            return false;
        }
        int c = toInt(s[0]);
        assert(child[c] != nullptr);
        if(child[c]->Delete(s + 1))
        {
            delete child[c];
            child[c] = nullptr;
            nrChildren--;
            if(cnt == 0 && nrChildren == 0)
                return true;
        }
        return false;
    }
    int Find(char *s)
    {
        if(s[0] == '\0')
            return cnt;
        int c = toInt(s[0]);
        if(child[c] == nullptr)
            return 0;
        return child[c]->Find(s + 1);
    }
    int Pref(char *s, int mx = 0)
    {
        char c = toInt(s[0]);
        if(s[0] == '\0' || child[c] == nullptr)
            return mx;
        return child[c]->Pref(s + 1, mx + 1);
    }
private:
    int cnt;
    int nrChildren;
    Trie * child[26];
};

int main()
{
    ifstream in("trie.in");
    ofstream out("trie.out");
    Trie t;
    int x;
    char cuv[25];
    while(in >> x && in >> cuv)
    {
        if(x == 0)
            t.Insert(cuv);
        else if(x == 1)
            t.Delete(cuv);
        else if(x == 2)
            out << t.Find(cuv) << "\n";
        else if(x == 3)
            out << t.Pref(cuv) << "\n";
    }
    return 0;
}