#include <bits/stdc++.h>
using namespace std;

struct trie {
    int son,cnt;
    trie* v[30];

    trie() {
        son = cnt = 0;
        for (int i = 0;i <= 28;i++)
            v[i] = nullptr;
    }
};
trie* root = new trie;

void add(int i, string& s, trie* node) {
    if (i == s.size()) {
        node->cnt++;
        return;
    }
    int ind = s[i] - 'a' + 1;
    if (!node->v[ind]) {
        node->son++;
        node->v[ind] = new trie;
    }
    add(i + 1, s, node->v[ind]);
}
bool check(trie* node) {
    return (!node->cnt && !node->son && node != root);
}
bool del(int i, string& s, trie* node) {
    if (i == s.size()) {
        if (node->cnt)
            node->cnt--;
        if (check(node)) {
            delete node;
            return true;
        }
        return false;
    }
    int ind = s[i] - 'a' + 1;
    if (del(i + 1, s, node->v[ind])){
        node->son--;
        node->v[ind] = nullptr;
    }
    if (check(node)) {
        delete node;
        return true;
    }
    return false;
}
int cnt(int i, string& s, trie* node) {
    if (i == s.size())
        return node->cnt;
    int ind = s[i] - 'a' + 1;
    if (!node->v[ind])
        return 0;
    return cnt(i + 1, s, node->v[ind]);
}
int pref(int i, string& s, trie* node) {
    if (i == s.size())
        return i;
    int ind = s[i] - 'a' + 1;
    if (!node->v[ind])
        return i;
    return pref(i + 1, s, node->v[ind]);
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    ifstream fin("trie.in");
    ofstream fout("trie.out");
    int op;
    string s;
    while (fin >> op >> s) {
        if (op == 0)
            add(0, s, root);
        else if (op == 1)
            del(0, s, root);
        else if (op == 2)
            fout << cnt(0, s, root) << '\n';
        else
            fout << pref(0, s, root) << '\n';
    }
    return 0;
}