#include <bits/stdc++.h>

using namespace std;

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

const int SIGMA = 26;
const int DIM = 20;

int type;
char text[DIM + 1];

struct Trie {
	int freq;
	int words;
	Trie* children[SIGMA];


	Trie() {
		freq = 0;
		words = 0;

		for(int i = 0; i < SIGMA; i++) {
			children[i] = nullptr;
		}
	}
};

Trie root;

void insert(Trie* root, char* text) {
	if(*text == '\0') {
		root->freq++;
		root->words++;
	} else {
		if(root->children[text[0] - 'a'] == nullptr) {
			root->children[text[0] - 'a'] = new Trie();
		}
		root->children[text[0] - 'a']->freq++;
		insert(root->children[text[0] - 'a'], text +  1);
	}
}

void erase(Trie* root, char* text) {
	if(*text == '\0') {
		root->freq--;
		root->words--;
	} else {
		if(root->children[text[0] - 'a'] != nullptr) {
			root->children[text[0] - 'a']->freq--;
			erase(root->children[text[0] - 'a'], text + 1);
		}
	}
}

int count(Trie* root, char* text) {
	if(*text == '\0') {
		return root->words;
	} else {
		if(root->children[text[0] - 'a'] == nullptr) {
			return 0;
		}

		if(root->children[text[0] - 'a']->freq == 0) {
			return 0;
		}

		return count(root->children[text[0] - 'a'], text + 1);
	}
}

int prefix(Trie* root, char* text, int cnt = 0) {
	if(*text == '\0') {
		return cnt;
	} else {
		if(root->children[text[0] - 'a'] == nullptr) {
			return cnt;
		}

		if(root->children[text[0] - 'a']->freq == 0) {
			return cnt;
		}

		return prefix(root->children[text[0] - 'a'], text + 1, cnt + 1);
	}
}

int main() {
	while(fin >> type >> text) {
		if(type == 0) {
			insert(&root, text);
		} else if(type == 1) {
			erase(&root, text);
		} else if(type == 2) {
			fout << count(&root, text) << '\n';
		} else if(type == 3) {
			fout << prefix(&root, text) << '\n';
		}
	}
	return 0;
}