#include <cstdio>
#include <cstring>
#include <fstream.h>
ifstream f("trie.in");

#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;

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() {
	char line[109];
	int w;

	
	freopen( "trie.out", "w", stdout );
	//f>>w;f.getline( line, 108, '\n');
	while (f.getline( line, 108, '\n'))
	{

	//f.getline( line, 108, '\n');
	line[strlen(line)]='\n';
	line[strlen(line)+1]='\0';
	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;
		}
	}
	printf("0");
	return 0;
}