#include <iostream>
#include <cstdio>
#include <fstream>
#include <string>
#include <cstring>
#include <algorithm>

using namespace std;

//ifstream f("trie.in");
ofstream g("trie.out");

struct trie {
    int cnt, nrfii;
    trie *a[26];
    trie() {
        cnt = nrfii = 0;
        memset(a, 0, sizeof(a));
    }
};
trie *T = new trie;

void ins(trie *nod, char *s) {
    if(*s == '\n') {
        nod -> cnt ++;
        return;
    }
    if(nod -> a[*s - 'a'] == 0) {
        nod -> a[*s - 'a'] = new trie;
        nod -> nrfii ++;
    }
    ins(nod -> a[*s - 'a'], s + 1);
}

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

int que(trie *nod, char *s) {
    if(*s == '\n')
        return nod -> cnt;

    if(nod -> a[*s - 'a']) {
        return que(nod -> a[*s - 'a'], s + 1);
    }
    return 0;
}

int pre(trie *nod, char *s, int k) {
    if(*s == '\n' || nod -> a[*s - 'a'] == 0)
        return k;
    return pre(nod -> a[*s - 'a'], s + 1, k + 1);
}

int main()
{
    freopen("trie.in", "r", stdin);

    char line[32];
    //f.get(line, 32);
    fgets(line, 32, stdin);

    while(!feof(stdin)) {
        //line[strlen(line)] = '\n';
        //g << line;
        switch(line[0]) {
            case '0': ins(T, line + 2); break;
            case '1': del(T, line + 2); break;
            case '2': g << que(T, line + 2) << '\n'; break;
            case '3': g << pre(T, line + 2, 0) << '\n'; break;
        }
        //f.get(line, 32);
        fgets(line, 32, stdin);
    }

    //f.close();
    g.close();
    return 0;
}