#include<cstdio>
#include<cstring>
#include<iostream>
#include<fstream>
#include<algorithm>
#include<vector>
using namespace std;

#define maxl 30

char s[maxl] ;
struct trie 
{
	int nr, nrfii ;
	trie *fiu[ maxl ];
	trie() 
	{
		nr = nrfii = 0 ;
		memset( fiu, 0, sizeof(fiu) ) ;
	}
} *T ;

void adauga(trie *nod, char *s )
{
	
	if( *s > 'z' || *s < 'a' ) 
	{
		nod -> nr++ ;
		return ;
	}
	
	if( nod -> fiu[ *s - 'a' ] == 0 ) 
	{
		nod -> fiu[ *s - 'a' ] = new trie ;
		nod -> nrfii++ ;
	}
	
	adauga( nod -> fiu[ *s - 'a' ], s + 1 ) ;

}

int sterge(trie *nod, char *s )
{
	
	if( *s > 'z' || *s < 'a' )
		nod -> nr-- ;	
	
	else 
	if( sterge( nod-> fiu[ *s - 'a' ], s + 1 ) == 1 ) 
	{
		nod -> fiu[ *s - 'a' ] = 0 ;
		nod -> nrfii-- ;
	}
	
	if( nod -> nr == 0 && nod -> nrfii == 0 && nod != T ) 
	{
		delete nod ;
		return 1 ;
	}
	
	return 0 ;

}

int aparitii(trie *nod,char *s)
{
	
	if( *s > 'z' || *s < 'a' )
		return nod -> nr ;
	
	if( nod -> fiu[ *s - 'a' ] )
		return aparitii( nod -> fiu[ *s - 'a' ], s + 1 ) ;
	
	return 0 ;
	
}

int prefix(trie *nod, char *s, int poz)
{
	
	if( *s > 'z' || *s < 'a' || nod -> fiu[ *s - 'a' ] == 0 )
		return poz ;
	
	return prefix( nod -> fiu[ *s - 'a' ], s + 1, poz + 1 ) ;

}

int main() 
{
	
	//freopen("trie.in", "r", stdin);
	//freopen("trie.out", "w", stdout);
	
	ifstream f("trie.in") ;
	ofstream g("trie.out") ;
	
	T = new trie ;
	
	while( cin>>s ) 
	{
		if( s[0] == '0' )
			adauga( T, s + 2 ) ;
		if( s[0] == '1' )
			sterge( T, s + 2 ) ;
		if( s[0] == '2' )
			g<< aparitii( T, s + 2 ) << '\n' ;
		if( s[0] == '3' )
			g<< prefix(T, s + 2, 0 ) << '\n' ;
	}

	return 0 ;
	
}