#include <bits/stdc++.h>

using namespace std;

ifstream fin("trie.in");
ofstream fout("trie.out");

struct Node
{
    int cnt, nrSons;
    Node *sons[26];
    Node()
    {
        cnt = 0;
        nrSons = 0;
        for (int i = 0; i < 26; i++)
            sons[i] = NULL;
    }
};

Node *Root = new Node;

int tip;
char s[25];

void Add(Node *T, char *s)
{
    if (s[0] == '\0')
    {
        T->cnt++;
        return;
    }
    else if (T->sons[s[0] - 'a'] == NULL)
    {
        T->nrSons++;
        T->sons[s[0] - 'a'] = new Node;
    }
    Add(T->sons[s[0] - 'a'], s + 1);
}

int Remove(Node *T, char *s)
{
    if (s[0] == '\0')
        T->cnt--;
    else if (Remove(T->sons[s[0] - 'a'], s + 1))
    {
        T->sons[s[0] - 'a'] = NULL;
        T->nrSons--;
    }
    if (T->cnt == 0 && T->nrSons == 0 && T != Root)
    {
        delete T;
        return 1;
    }
    return 0;
}

int Count(Node *T, char *s)
{
    if (s[0] == '\0')
        return T->cnt;
    else if (T->sons[s[0] - 'a'] == NULL)
        return 0;
    else
        return Count(T->sons[s[0] - 'a'], s + 1);
}

int MaxPre(Node *T, char *s)
{
    if (s[0] == '\0')
        return 1;
    if (T->sons[s[0] - 'a'])
        return 1 + MaxPre(T->sons[s[0] - 'a'], s + 1);
    else
        return 0;
}

int main()
{
    while (fin >> tip >> s)
    {
        if (tip == 0)
            Add(Root, s);
        else if (tip == 1)
            Remove(Root, s);
        else if (tip == 2)
            fout << Count(Root, s) << "\n";
        else
            fout << MaxPre(Root, s) << "\n";
    }
    return 0;
}