#include <fstream>
#include <string>
using namespace std;
struct TRIE
{
	int f,nre;
	TRIE *E[26];
	TRIE()
	{
		f=nre=0;
		for(int i=0;i<26;i++)
			E[i]=0;
	}
};
ifstream fi("trie.in");
ofstream fo("trie.out");
int tip;
string s;
TRIE *T=new TRIE;
void adauga(TRIE *nod,string s)
{
	if(s.empty())
	{
		nod->f++;
		return;
	}
	if(!nod->E[s[0]-'a'])
	{
		nod->E[s[0]-'a']=new TRIE;
		nod->nre++;
	}
	int x=s[0]-'a';
	s.erase(s.begin());
	adauga(nod->E[x],s);
}
int sterge( TRIE *nod, string s )
{
	int x;
    if(s.empty())
        nod->f --;
    else
    {
		if(!s.empty())
		{
			x=s[0]-'a';
			s.erase(s.begin());
		} 
	    if( sterge( nod->E[x], s) )
	    {
	        nod->E[x] = 0;
	        nod->nre --;
	    }
	}
    if( nod->f == 0 && nod->nre == 0 && nod != T )
    {
        delete nod;
        return 1;
    }
    return 0;
}
int nraparitii(TRIE *nod,string s)
{
	if(s.empty())
		return nod->f;
	int x=s[0]-'a';
	s.erase(s.begin());
	if(nod->E[x])
		return nraparitii(nod->E[x],s);
	return 0;
}
int nrprefixe(TRIE *nod,string s,int k)
{
	int x=s[0]-'a';
	s.erase(s.begin());
	if(s.empty()|| !nod->E[x])
		return k;
	return nrprefixe(nod->E[x],s,k+1);
}
int main()
{
	while(fi>>tip)
	{
		fi>>s;
		if(tip==0)
			adauga(T,s);
		else if(tip==1)
			sterge(T,s);
		else if(tip==2)
			fo<<nraparitii(T,s)<<"\n";
		else
			fo<<nrprefixe(T,s,0)<<"\n";
	}
	fi.close();
	fo.close();
	return 0;
}