#include <bits/stdc++.h>
#define CH (*s - 'a')

using namespace std;

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

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

Trie* T = new Trie;

void Insert(Trie *nod, char *s) {
	if(*s == '\n') {
		++nod -> cnt;
		return;
	}
	if(nod -> fiu[CH] == 0) {
		nod -> fiu[CH] = new Trie;
		++nod -> nrfii;
	}
	Insert(nod -> fiu[CH], s + 1);
}

bool Delete(Trie *nod, char *s) {
	if(*s == '\n')
		--nod -> cnt;
	else
        if(Delete(nod -> fiu[CH], s + 1)) {
			nod -> fiu[CH] = 0;
			--nod -> nrfii;
		}
	if(nod -> cnt == 0 && nod -> nrfii == 0 && nod != T) {
		delete nod;
        return true;
	}
	return false;
}

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

int Preffix(Trie *nod, char *s, int k) {
	if(*s == '\n' || nod -> fiu[CH] == 0)
		return k;
	return Preffix(nod -> fiu[CH], s + 1, k + 1);
}

int main() {
	short op;
    char s[32];
    while(fin >> op) {
        fin >> s;
        s[strlen(s)] = '\n';
        if(op == 0)
            Insert(T, s);
        if(op == 1)
            Delete(T, s);
        if(op == 2)
            fout << Count(T, s) << '\n';
        if(op == 3)
            fout << Preffix(T, s, 0) << '\n';
    }
}