#include <iostream>
#include <fstream>
#include <stdint.h>

const int32_t MAX_LEN = 20;
const int32_t MAX_OP_COUNT = 100000;
const int32_t MAX_NODE_COUNT = 500000;

struct Node {
	int32_t count;
	int32_t childCount;
	Node* children[26];
};

Node nodeList[MAX_NODE_COUNT];
Node* tree;
Node* freeList;

void Insert(char* str) {
	Node* node = tree;
	for(; *str; ++str) {
		int32_t ind = *str - 'a';

		if(!node->children[ind]) {
			Node* newNode = freeList;
			freeList = newNode->children[0];
			newNode->children[0] = nullptr;

			node->children[ind] = newNode;
			++node->childCount;
		}

		node = node->children[ind];
	}
	++node->count;
}
void Erase(char* str) {
	Node* node = tree;

	Node* stack[MAX_LEN + 1];
	int32_t inds[MAX_LEN + 1];
	int32_t top = 1;

	stack[top] = tree;
	inds[top] = -1;
	
	for(; *str; ++str) {
		int32_t ind = *str - 'a';
		node = node->children[ind];

		stack[top] = node;
		inds[top] = ind;
		++top;
	}

	--node->count;
	--top;
	for(; top; --top) {
		if(stack[top]->count || stack[top]->childCount)
			break;
		
		stack[top - 1]->children[inds[top]] = nullptr;
		--stack[top - 1]->childCount;

		for(int32_t i = 1; i != 26; ++i)
			stack[top]->children[i] = nullptr;
		stack[top]->children[0] = freeList;
		freeList = stack[top];
	}
}
int32_t Find(char* str) {
	Node* node = tree;
	for(; *str; ++str) {
		int32_t ind = *str - 'a';

		if(!node->children[ind])
			return 0;
		
		node = node->children[ind];
	}

	return node->count;
}
int32_t Prefix(char* str) {
	Node* node = tree;
	int32_t len = 0;
	for(; str[len]; ++len) {
		int32_t ind = str[len] - 'a';

		if(!node->children[ind])
			break;
		
		node = node->children[ind];
	}

	return len;
}

int main() {
	std::ifstream fin("trie.in");
	std::ofstream fout("trie.out");

	tree = nodeList;
	freeList = nodeList + 1;
	for(int32_t i = 1; i != MAX_NODE_COUNT - 1; ++i)
		nodeList[i].children[0] = nodeList + i + 1;
	nodeList[MAX_NODE_COUNT - 1].children[0] = nullptr;

	int32_t c;
	char str[MAX_LEN + 1];
	while(fin >> c) {
		fin >> str;

		switch(c) {
		case 0:
			Insert(str);
			break;
		case 1:
			Erase(str);
			break;
		case 2:
			fout << Find(str) << '\n';
			break;
		case 3:
			fout << Prefix(str) << '\n';
			break;
		}
	}

	fin.close();
	fout.close();

	return 0;
}