#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast")

using namespace std;

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

int type;
string word;

struct trie{
    int lcnt, terminal;
    trie *leaf[26];

    trie(){
        lcnt = terminal = 0;
        for(int i=0; i < 26; i++)
            leaf[i] = NULL;
    }
} *tr = new trie;

inline void update(trie *nod, int index, int limit, int modif){
    int letter = word[index] - 'a';

    nod->lcnt += modif;
    if(index < limit){

        if(nod->leaf[letter] == NULL)
            nod->leaf[letter] = new trie;

        update(nod->leaf[letter], index+1, limit, modif);
    }else
        nod->terminal += modif;
}

inline int get_freq(trie *nod, int index, int limit){
    int letter = word[index] - 'a';

    if(index < limit){

        if(nod->leaf[letter] == NULL || nod->leaf[letter]->lcnt == 0)
            return 0;

        return get_freq(nod->leaf[letter], index+1, limit);
    }else
        return nod->terminal;
}

inline int prefix(trie *nod, int index, int limit){
    int letter = word[index] - 'a';

    if(index < limit){

        if(nod->leaf[letter] == NULL || nod->leaf[letter]->lcnt == 0)
            return index;

        return prefix(nod->leaf[letter], index+1, limit);
    }else
        return index;
}

int main (){
    ios_base::sync_with_stdio(false);
    fin.tie(nullptr), fout.tie(nullptr);

    while(fin>>type){
        fin>>word;

        if(type == 0) /// add word
            update(tr, 0, (int)word.size(), +1);

        if(type == 1) /// rem word
            update(tr, 0, (int)word.size(), -1);

        if(type == 2) /// query freq
            fout<<get_freq(tr, 0, (int)word.size())<<"\n";

        if(type == 3) /// query prefix
            fout<<prefix(tr, 0, (int)word.size())<<"\n";
    }
    return 0;
}