#include <string>
#include <fstream>
using namespace std;

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

struct Node {
	int descendants;
	int words;

	Node* sons[26];

	Node(void) {
		descendants = words = 0;
		for (unsigned int i = 0; i < 26; ++i)
			sons[i] = NULL;
	}
};

Node* root = new Node();

void InsertNode(Node*, const string&, unsigned int = 0);
bool EraseNode(Node*, const string&, unsigned int = 0);
int CountWords(Node*, const string&, unsigned int = 0);
int CountPrefix(Node*, const string&, unsigned int = 0);

int main()
{
	int number; string word;

	while ( fin >> number >> word )
	{
		if ( number == 0 )
			InsertNode(root, word);
		if ( number == 1 )
			EraseNode(root, word);
		if ( number == 2 ) fout <<
			CountWords(root, word) << '\n';
		if ( number == 3 ) fout <<
			CountPrefix(root, word) << '\n';
	}

	fin.close();
	fout.close();
	return 0;
}

int CountPrefix(Node* node, const string& word, unsigned int depth)
{
	if ( depth == word.size() )
		return depth;
	else
	{
		int son_position = word[depth] - 'a';
		Node* son = node->sons[son_position];

		if ( node->sons[son_position] != NULL )
			return CountPrefix(node->sons[son_position], word, depth+1);
		return depth;
	}
}

int CountWords(Node* node, const string& word, unsigned int depth)
{
	if ( depth == word.size() )
		return node->words;

	int son_position = word[depth] - 'a';

	if ( node->sons[son_position] != NULL )
		return CountWords(node->sons[son_position], word, depth+1);
	return 0;
}

bool EraseNode(Node* node, const string& word, unsigned int depth)
{

	int son_position = word[depth] - 'a';

	if ( depth == word.size() )
		--node->words;
	else if ( EraseNode(node->sons[son_position], word, depth+1) )
	{
		--node->descendants;
		node->sons[son_position] = NULL;
	}
	if ( node->words == 0 && node->descendants == 0 && node != root )
	{
		delete node;
		return true;
	}

	return false;
}

void InsertNode(Node* node, const string& word, unsigned int depth)
{
	if ( depth == word.size() )
	{
		++node->words;
		return;
	}

	int son_position = word[depth] - 'a';

	if ( node->sons[son_position] == NULL )
	{
		node->sons[son_position] = new Node();
		++node->descendants;
	}
	InsertNode(node->sons[son_position], word, depth+1);
}