#include <fstream>
#include <vector>
#include <unordered_map>

using namespace std;

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


class Trie{
private:
		unordered_map<char, Trie*> edge;
		int cnt = 0;
		int cntFinal = 0;

		inline Trie* getEdge(char ch){
			auto it = edge.find(ch);
			if(it != edge.end())
				return it->second;
			return nullptr;
		}

		inline Trie* addEdge(char ch){
			Trie* edg = getEdge(ch);
			if(edg == nullptr){
				edge.insert({ch, new Trie()});
				edg = edge[ch];
			}

			return edg;
		}

		bool isFinal(){
			return cntFinal;
		}

public:

		void insert(const char* word){
			int i = 0;
			++this->cnt;
			Trie* current = this;
			while(word[i]){
				current = current->addEdge(word[i]);
				++current->cnt;
				++i;
			}

			++current->cntFinal;
		}

		void erase(const char* word){
			int i = 0;
			Trie* current = this;
			while(word[i]){
				current = current->getEdge(word[i]);
				--current->cnt;
				++i;
			}


			if(current->cnt == 0){
				i = 0;
				Trie* ant;
				current = this;
				while(word[i] && current->cnt > 0){
					ant = current;
					current = current->getEdge(word[i]);
					++i;
				}

				ant->edge.erase(word[i - 1]);
				delete current;
			}
		}

		int count(const char* word){
			int i = 0;
			Trie* current = this;
			while(word[i] && current != nullptr){
				current = current->getEdge(word[i]);
				++i;
			}

			if(current != nullptr && current->isFinal())
				return current->cntFinal;
			else
				return 0;
		}

		int longestPrefix(const char* word){
			int i = 0;
			Trie* current = this;
			while(word[i] && current != nullptr && current->cnt > 0){
				current = current->getEdge(word[i]);
				++i;
			}

			return i - 1;
		}
};

const int STRLEN_MAX = 20;
int op;
char word[STRLEN_MAX + 1];
Trie trie;

int main(){

	while(fin >> op >> word)
		switch(op){
			case 0:{
				trie.insert(word);
				break;
			}
			case 1:{
				trie.erase(word);
				break;
			}
			case 2:{
				fout << trie.count(word) << '\n';
				break;
			}
			case 3:{
				fout << trie.longestPrefix(word) << '\n';
				break;
			}
		}

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