//#include <fstream>
#include <stdio.h>
#include <stdlib.h>
		
using namespace std;
		
//ifstream in("trie.in");
//ofstream out("trie.out");
	
class Node	
{	
public:
    int nr_a = 0;
    int nr_c = 0;
	
    Node* fii[26] {nullptr};
};	
	
class Trie	
{	
    Node* root = nullptr;
public:
    void insert(char* s)	
    {
        root = insert_(s, root);
    }	
	
    void erase(char* s)
    {
        root = erase_(s, root);
    }
	
    int query_prefix(char* s)	
    {	
        return query_prefix_(s, root);
    }
	
    int query_cuvant(char* s)	
    {
        return query_cuv_(s, root);
    }
	
private:
    int query_prefix_(char* s, Node* node);	
    int query_cuv_(char* s, Node* node);	
    Node* insert_(char* s, Node* node);	
    Node* erase_(char* s, Node* node);	
};	
	
Node* Trie::insert_(char* s, Node* node)	
{
    if(node == nullptr)	
    {
        node = new Node();
    }
	
    node->nr_a++;
	
    if(s[0] == '\0' || s[0] == '\n')
    {
        node->nr_c++;
        return node;
    }
    else
    {
        node->fii[s[0] - 'a'] = insert_(s + 1, node->fii[s[0] - 'a']);
    }
		
    return node;	
}
	
Node* Trie::erase_(char* s, Node* node)	
{	
    if(node == nullptr)	
    {	
        return node;	
    }	
	
    node->nr_a--;	
	
    if(s[0] == '\0' || s[0] == '\n')	
    {	
        node->nr_c--;	
    }	
    else	
    {	
      node->fii[s[0] - 'a'] = erase_(s + 1, node->fii[s[0] - 'a']);	
    }	
	
    if(node->nr_a == 0)	
    {	
        delete node;	
        node = nullptr;	
    }
	
    return node;	
}	
	
int Trie::query_prefix_(char* s, Node* node)	
{	
    if(s[0] == '\0' || s[0] == '\n' || node == nullptr || node->fii[s[0] - 'a'] == nullptr)	
        return 0;

    return query_prefix_(s + 1, node->fii[s[0] - 'a']) + 1;	
}
	
int Trie::query_cuv_(char* s, Node* node)	
{	
    if(node == nullptr)	
    {
        return 0;	
    }
    else if(s[0] == '\0' || s[0] == '\n')	
        return node->nr_c;	
    else
        return query_cuv_(s + 1, node->fii[s[0] - 'a']);	
}	 
	
Trie arbore;
	
char* s;
	
int main()	
{	
    freopen("trie.in", "r", stdin);	
    freopen("trie.out", "w", stdout);

    size_t size = 25;
    s = (char *)malloc(size);
    while(getline(&s, &size, stdin) >= 0)	
    {     	
        switch(s[0])
        {
            case '0':
                arbore.insert(s + 2);
                break;
	
            case '1':
                arbore.erase(s + 2);
                break;
	
            case '2':
                printf("%d cuvant\n", arbore.query_cuvant(s + 2));
                break;
	
            case '3':
                printf("%d prefix\n", arbore.query_prefix(s + 2));
                break;
        }
    }
}