#include <fstream>
#include <vector>
#include <string.h>
#include <stdlib.h>

using namespace std;

class Node {
public:
	vector<Node *> neighbours;
	int freq, branches;

	Node() : neighbours(26, NULL), freq(0), branches(0) {}
	~Node() {}

	void insert(char * word) {
		if (*word == '\0') {
			++freq;
			return;
		}

		int index = word[0] - 'a';
		if (neighbours[index] == NULL) {
			neighbours[index] = new Node();
			++branches;
		}
		neighbours[index]->insert(word + 1);
	}

	bool remove(char * word) {
		int index = word[0] - 'a';
		
		if (*word == '\0') {
			--freq;
		} else if (neighbours[index] != NULL) {
			if (neighbours[index]->remove(word + 1)) {
				delete neighbours[index];
				neighbours[index] = NULL;
				--branches;
			}
		} else {
			return false;
		}

		return freq == 0 && branches == 0;
	}

	int frequency(char * word) {
		if (*word == '\0') {
			return freq;
		}

		int index = word[0] - 'a';
		if (neighbours[index] != NULL) {
			return neighbours[index]->frequency(word + 1);
		} else {
			return 0;
		}
	}

	int longestPrefix(char * word, int length) {
		if (*word == '\0' || neighbours[word[0] - 'a'] == NULL)
			return length;
	
		int index = word[0] - 'a';	
		return neighbours[index]->longestPrefix(word + 1, length + 1);	
	}
};

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

Node * root;
string word;
int op;
char * w;

int main() {
	root = new Node();

	while (true) {
		fin >> op >> word;
		w = strdup(word.c_str());
		if (fin.eof())
			break;

		if (op == 0) {
			root->insert(w);
		} else if (op == 1) {
			root->remove(w);
		} else if (op == 2) {
			fout << root->frequency(w) << '\n';
		} else if (op == 3) {
			fout << root->longestPrefix(w, 0) << '\n';
		}
		free(w);
	}

	return 0;
}