#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

struct Trie {
	int num, numChildren;
	vector<Trie*> children;

	Trie(int a) {
		num = 0;
		numChildren = 0;
		
		children.resize(26);
		for(int i=0; i<26; ++i)
			children[i] = NULL;
	}

	void add(string::iterator i, string::iterator j);
	void remove(string::iterator i, string::iterator j);
	int count(string::iterator i, string::iterator j);
	int getMaxPrefLength(string::iterator i, string::iterator j);
};

void Trie::add(string::iterator i, string::iterator j) {
	if(i == j) {
		++num;	
	} else {
		if(children[*i - 'a'] == NULL) {
			children[*i - 'a'] = new Trie(0);
			++numChildren;
		}
		children[*i - 'a'] -> add(i+1, j);
	}	
}

void Trie::remove(string::iterator i, string::iterator j) {
	if(i == j) {
		--num;
	} else {
		children[*i - 'a'] -> remove(i+1, j);
		if(children[*i - 'a'] -> num == 0 && children[*i - 'a'] -> numChildren == 0) {
			delete children[*i - 'a'];
			children[*i - 'a'] = NULL;
			--numChildren;
		}
	}
}

int Trie::count(string::iterator i, string::iterator j) {
	if(i == j) {
		return num;	
	} else {
		if(children[*i - 'a'] != NULL) {
			return children[*i - 'a'] -> count(i+1, j);
		} else 
			return 0;	
	}	
}

int Trie::getMaxPrefLength(string::iterator i, string::iterator j) {
	if(children[*i - 'a'] != NULL && i != j) {
		return children[*i -'a'] -> getMaxPrefLength(i+1, j) + 1;
	} else
		return 0;
}

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

	int q;
	string w;
	
	Trie trie(0);
	
	while(!fin.eof()) {
		fin >> q >> w;
		switch (q) {
			case 0: {
				trie.add(w.begin(), w.end()); 
				break;
			}
			case 1: {
				trie.remove(w.begin(), w.end());
				break;
			}
			case 2: {
				fout << trie.count(w.begin(), w.end()) << '\n';
				break;
			}
			case 3: {
				fout << trie.getMaxPrefLength(w.begin(), w.end()) << '\n';
				break;
			}				 					
		}		
	}		

	return 0;
}