#include <cstdio>
#include <cstring>

using namespace std;

struct Trie {
    int cnt, nr_fii;
    Trie *son[26];
    Trie() {
        cnt = nr_fii = 0;
        memset(son, 0 ,sizeof(son));
    }
};

Trie *T = new Trie;
char line[23];

void ins(Trie *nod, char *s) {
    if (*s == '\n') {
        nod->cnt++;
        return;
    }
    if (nod->son[*s - 97] == 0) {
        nod->son[*s - 97] = new Trie;
        nod->nr_fii++;
    }
    ins(nod->son[*s - 97], s + 1);
}

int del(Trie *nod, char *s){
    if (*s == '\n')
        nod->cnt--;
    else
    if (del(nod->son[*s - 97], s + 1)) {
        nod->son[*s - 97] = 0;
        nod->nr_fii--;
    }
    if (nod->cnt == 0 && nod->nr_fii == 0 && nod != T) {
        delete nod;
        return 1;
    }
    return 0;
}

int freq(Trie *nod, char *s) {
    if (*s == '\n')
        return nod->cnt;
    if (nod->son[*s - 97])
        return freq(nod->son[*s - 97], s + 1);
    return 0;
}

int prefix(Trie *nod, char *s, int k) {
    if (*s == '\n' or nod->son[*s - 97] == 0)
        return k;
    return prefix(nod->son[*s - 97], s + 1, k + 1);
}

int main() {

    freopen( "trie.in", "r", stdin );
    freopen( "trie.out", "w", stdout );

    fgets( line, 23, stdin );

    while( !feof( stdin ) ) {
        switch( line[0] ) {
            case '0': ins( T, line+2 ); break;
            case '1': del( T, line+2 ); break;
            case '2': printf( "%d\n", freq( T, line+2 ) ); break;
            case '3': printf( "%d\n", prefix( T, line+2, 0 ) ); break;
        }

        fgets( line, 32, stdin );
    }
    return 0;
}