#include <fstream>
#include <string>
#include <vector>

using namespace std;

class Trie {
		struct Node
		{
			int cnt = 0, lvs = 0;
			int next[26] = {};
		};
		vector<Node> trie;

	public:
		inline Trie() noexcept
			: trie (1) {}

		inline void insert (const string& str) {
			int node = 0;

			for (const char chr : str) {
				if (trie[node].next[chr - 'a'] == 0) {
					trie[node].next[chr - 'a'] = trie.size();
					trie.emplace_back();
				}

				node = trie[node].next[chr - 'a'];
				++trie[node].lvs;
			}

			++trie[node].cnt;
		}

		inline void erase (const string& str) {
			int node = 0;

			for (const char chr : str) {
				node = trie[node].next[chr - 'a'];
				--trie[node].lvs;
			}

			--trie[node].cnt;
			node = 0;

			for (const char chr : str) {
				if (trie[trie[node].next[chr - 'a']].lvs == 0) {
					trie[node].next[chr - 'a'] = 0;
					return;
				}

				node = trie[node].next[chr - 'a'];
			}
		}

		inline int count (const string& str) {
			int node = 0;

			for (const char chr : str) {
				if (trie[node].next[chr - 'a'] == 0)
					return 0;

				node = trie[node].next[chr - 'a'];
			}

			return trie[node].cnt;
		}

		inline int lcp (const string& str) {
			int node = 0, len = 0;

			for (const char chr : str) {
				if (trie[node].next[chr - 'a'] == 0)
					return len;

				node = trie[node].next[chr - 'a'];
				++len;
			}

			return len;
		}
};

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

int main()
{
	Trie trie;
	int task;
	string str;

	while (fin >> task >> str)
	{
		if (task == 0)
			trie.insert (str);
		else if (task == 1)
			trie.erase (str);
		else if (task == 2)
			fout << trie.count (str) << '\n';
		else
			fout << trie.lcp (str) << '\n';
	}

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