#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct trie {
	int n;
	char dim;
	struct trie *next[26];
} TrieCell, *Trie;

Trie t;

void add (const char *s) {
	Trie current = t;
	
	while (*s != '\0') {
		if (!current->next[*s-'a']) {
			current->next[*s-'a'] = (Trie) calloc(1, sizeof(TrieCell));
			++current->dim;
		}
		
		current = current->next[*s-'a'];
		++s;
	}
	
	++current->n;
}

void remove (Trie *current, const char *s) {
	if (*s == '\0') {
		--(*current)->n;
		if (!(*current)->n && !(*current)->dim) {
			free(*current);
			(*current) = NULL;
		}
		 
		return;
	}
	
	remove(&(*current)->next[*s-'a'], s+1);
	
	if (!(*current)->next[*s-'a']) {
		--(*current)->dim;
		if (!(*current)->n && !(*current)->dim) {
			free(*current);
			(*current) = NULL;
		}
	}
}

int count (const char *s) {
	Trie current = t;
	
	while (*s != '\0') {	
		if (!current->next[*s-'a']) {
			return 0;
		}
			
		current = current->next[*s-'a'];
		++s;
	}
	
	return current->n;
}

int prefixLen (const char *s) {
	Trie current = t;
	
	int i = 0;
	
	while (*s != '\0') {
		if (current->next[*s-'a']) {
			current = current->next[*s-'a'];
		} else {
			break;
		}
		
		++i;
		++s;
	}
	
	return i;
}

int main(void) {
	freopen("trie.in", "r", stdin);
	freopen("trie.out", "w", stdout);
	
	t = (Trie) calloc(1, sizeof(TrieCell));
	
	char buffer[1000];
	
	while (fgets(buffer, 1000, stdin)) {
		buffer[strlen(buffer)-1] = '\0';
		char op = buffer[0];
		switch (op) {
			case '0': add(buffer+2); break;
			case '1': remove(&t, buffer+2); break;
			case '2': printf("%d\n", count(buffer+2)); break;
			case '3': printf("%d\n", prefixLen(buffer+2)); break;
		}
	}
	
	return 0;
}