#include <cstdio>
#include <cstring>
#include <algorithm>
#define maxN 130002
#define maxL 22
#define sigma 26
using namespace std;
int n, i, j, r, tsize = 1, st[maxN], top;
char w[maxL];
typedef struct
{
    int c[sigma], p;
    unsigned short val;
    char nc;
} trie;
trie t[maxN];
void insert(char *s)
{
    int ind = 1, C;
    for ( ; *s; ++ s)
    {
        C = *s - 'a';
        if (!t[ind].c[C])
        {
            if (top)
            {
                t[ind].c[C] = st[top];
                -- top;
            }
            else
                t[ind].c[C] = ++ tsize;
            t[t[ind].c[C]].p = ind;
            ++ t[ind].nc;
        }
        ind = t[ind].c[C];
    }
    ++ t[ind].val;
}
void erase(char *s)
{
    int ind = 1;
    for (; *s; s++)
        ind = t[ind].c[*s - 'a'];
    -- t[ind].val;
    while (!t[ind].val && !t[ind].nc && (ind != 1))
    {
        -- s;
        st[++ top] = ind;
        ind = t[ind].p;
        t[ind].c[*s - 'a'] = 0;
        -- t[ind].nc;
    }
}
int count(char *s)
{
    int ind = 1;
    while (*s && t[ind].c[*s - 'a'])
    {
        ind = t[ind].c[*s - 'a'];
        ++ s;
    }
    if (*s)
        return 0;
    return t[ind].val;
}
int prefix(char *s)
{
    int ind = 1;
    char *S = s;
    while (*s && t[ind].c[*s - 'a'])
    {
        ind = t[ind].c[*s - 'a'];
        ++ s;
    }
    return s - S;
}
void rsw()
{
    freopen("trie.in", "r", stdin);
    freopen("trie.out", "w", stdout);
    while (1)
    {
        r = -1;
        scanf("%d %s\n", &r, &w);
        if (r == -1)
            return ;
        if (r == 0)
            insert(w);
        else
        if (r == 1)
            erase(w);
        else
        if (r == 2)
            printf("%d\n", count(w));
        else
            printf("%d\n", prefix(w));
    }
}
int main()
{
    rsw();
    return 0;
}