#include <fstream>
#include <cstring>
using namespace std;

ifstream is ("trie.in");
ofstream os ("trie.out");

struct Node{
    int NrAp, NrS;
    Node *Son[27];
    Node()
    {
        NrAp = NrS = 0;
        memset(Son, 0, sizeof(Son));
    }
};

Node *Root = new Node;
int OP;
char w[22];

void Add(char *w, Node *X);
bool Erase(char *w, Node *X);
int Count(char *w, Node *X);
int Prefix(char *w, Node *X, int k);

int main()
{
    while (is >> OP >> w)
    {
        if (OP == 0)
            Add(w, Root);
        if (OP == 1)
            Erase(w, Root);
        if (OP == 2)
            os << Count(w, Root) << '\n';
        if (OP == 3)
            os << Prefix(w, Root, 0) << '\n';
    }
}

void Add(char *w, Node *X)
{
    if (*w == 0)
    {
        X->NrAp++;
        return;
    }
    if (X->Son[*w - 'a'] == 0)
    {
        X->Son[*w - 'a'] = new Node;
        X->NrS++;
    }
    Add(w+1, X->Son[*w - 'a']);
}

bool Erase(char *w, Node *X)
{
    if (*w == 0)
        X->NrAp--;
    else
        if (Erase(w+1, X->Son[*w - 'a']) == 1)
        {
            X->NrS--;
            X->Son[*w - 'a'] = 0;
        }

    if (X != Root && X->NrS == 0 && X->NrAp == 0)
    {
        delete X;
        return 1;
    }
    return 0;
};

int Count(char *w, Node *X)
{
    if (*w == 0)
        return X->NrAp;
    if (X->Son[*w - 'a'])
        return Count(w+1, X->Son[*w - 'a']);
    return 0;
};

int Prefix(char *w, Node *X, int k)
{
    if (*w == 0)
        return k;
    if (X->Son[*w - 'a'])
        return Prefix(w+1, X->Son[*w - 'a'], k+1);
    return k;
};