#include <iostream>
#include <cstdio>
#include <cstring>
 
#define CH (*s - 'a')
 
using namespace std;
 
struct Trie {
	int cnt, nrfii;
	Trie *fiu[ 26 ];
 
	Trie() {
		cnt = nrfii = 0;
		memset( fiu, 0, sizeof( fiu ) );
	}	
};	
 
Trie *T = new Trie;	
char line[ 32 ];
 
void ins( Trie *nod, char *s ) {
	if( *s == '\n' ) {
		nod->cnt ++; return;
	}	
 
	if( nod->fiu[ CH ] == 0 ) {
		nod->fiu[ CH ] = new Trie;
		nod->nrfii ++;
	}	
 
	ins( nod->fiu[ CH ], s+1 );	
}	
 
int del( Trie *nod, char *s ) {
	if( *s == '\n' )
		nod->cnt --;
	else if( del( nod->fiu[ CH ], s+1 ) ) {
			nod->fiu[ CH ] = 0;
			nod->nrfii --;
		}	
 
	if( nod->cnt == 0 && nod->nrfii == 0 && nod != T ) {
		delete nod; return 1;
	}
	return 0;	
}	
 
int que( Trie *nod, char *s ) {
	if( *s == '\n' )
		return nod->cnt;	
 
	if( nod->fiu[ CH ] )
		return que( nod->fiu[ CH ], s+1 );
	return 0;
}	
 
int pre( Trie *nod, char *s, int k ) {
	if( *s == '\n' || nod->fiu[ CH ] == 0 )
		return k;
	return pre( nod->fiu[ CH ], s+1, k+1 );	
}	
 
int main() {
	
	freopen( "trie.in", "r", stdin );
	freopen( "trie.out", "w", stdout );	
 
	fgets( line, 32, stdin );	
 
	while( !feof( stdin ) ) {
		switch( line[0] ) {
			case '0': ins( T, line+2 ); break;
			case '1': del( T, line+2 ); break;
			case '2': printf( "%d\n", que( T, line+2 ) ); break;
			case '3': printf( "%d\n", pre( T, line+2, 0 ) ); break;
		}
		fgets( line, 32, stdin );
	}
	return 0;
}