#include <iostream>
#include <fstream>
#include <string>
using namespace std;
class trie
{
	struct node
	{
		int nr_sons, nr_words;
		node *sons[26];
		node()
		{
			nr_sons = nr_words = 0;
			for(int i = 0; i < 26; ++i)
				sons[i] = NULL;
		}
	};
	node *root;	
	public:
		trie()
		{
			root = new node;
		}
	private:
		void t_push(string str, node *here)
		{
			if(str.size() == 0)
			{
				here -> nr_words++;
				return;
			}
			if(here -> sons[str[0] - 97] == NULL)
			{
				here -> sons[str[0] - 97] = new node;
				here -> nr_sons++;
			}
			t_push(str.substr(1, str.size() - 1), here -> sons[str[0] - 97]);
		}
		bool t_pop(string str, node *here)
		{
			if(str.size() == 0)
				here -> nr_words--;
			else if(t_pop(str.substr(1, str.size() - 1), here -> sons[str[0] - 97]))
			{
				here -> sons[str[0] - 97] = NULL;
				here -> nr_sons--;
			}
			
			/*This node is no more necessary - has 0 sons and 0 words ending in it.*/
			if(here -> nr_words == 0 && here -> nr_sons == 0 && here != root)
			{
				delete here;
				return true;
			}
			return false;
		}
	public:
		void push(string str)
		{
			t_push(str, root);
		}
		void pop(string str)
		{
			t_pop(str, root);
		}
		int count(string str)
		{
			node *here = root;
			int i = 0;
			while(i < str.size())
			{
				if(here -> sons[str[i] - 97] == NULL)
					return 0;
				here = here -> sons[str[i] - 97];
				++i;
			}
			return here -> nr_words;
		}
		int longest_prefix(string str)
		{
			int max = 0;
			node *here = root;
			int i = 0;
			while (i < str.size())
			{
				if(here -> sons[str[i] - 97] == NULL)
					return max;
				here = here -> sons[str[i] - 97];
				max++;
				i++;
			}
			return max;			
		}
		
};
int main()
{
	trie tr;
	int op;
	string str;
	ifstream in("trie.in");
	ofstream out("trie.out");
	while(in >> op >> str)
	{
		switch(op)
		{
			case 0: tr.push(str); break;
			case 1: tr.pop(str); break;
			case 2: out << tr.count(str) << "\n"; break;
			case 3: out << tr.longest_prefix(str) << "\n"; break;
		}
	}
	in.close();
	out.close();
	return 0;	
}