/* 
 * File:   main.cpp
 * Author: virtualdemon
 *
 * Created on May 9, 2010, 8:44 AM
 */
#include <cstdlib>
#include <fstream>
#include <algorithm>

/*
 * 
 */
using namespace std;
typedef char* str;
class trie
{
    trie* t[30];
    int CountA, CountS;
    inline bool IsNC( char x )
    {
        return x < 'a' || x > 'z';
    }
    inline int GetV( char x )
    {
        return x-'a';
    }
public:
    trie( void ) : CountA(0), CountS(0)
    {
        for( int i=0; i < 30; ++i )
            t[i]=NULL;
    }
    inline void Add( str );
    inline bool Del( str );
    inline int CountWordA( str );
    inline int MaxLongPrefix( str, int&  );
} *root;
inline void trie::Add( str s )
{
    if( IsNC(s[0]) )
    {
        ++this->CountA;
        return;
    }
    int c=GetV(s[0]);
    if( NULL == this->t[c] )
        this->t[c]=new trie, ++this->CountS;
    this->t[c]->Add( s+1 );
}
inline bool trie::Del( str s )
{
    if( IsNC(s[0]) )
    {
        --this->CountA;
    }
    else {
            int c=GetV(s[0]);
            if( this->t[c]->Del(s+1) )
            {
                --this->CountS;
                this->t[c]=NULL;
            }
         }
    if( 0 == this->CountS && 0 == this->CountA )
        return true;
    return false;
}
inline int trie::CountWordA( str s )
{
    if( IsNC(s[0]) )
        return this->CountA;
    int c=GetV(s[0]);
    if( NULL == this->t[c] )
        return 0;
    return this->t[c]->CountWordA( s+1 );
}
inline int trie::MaxLongPrefix( str s, int& l )
{
    if( IsNC(s[0]) )
        return l;
    int c=GetV(s[0]);
    if( NULL == this->t[c] )
        return l;
    ++l;
    return this->t[c]->MaxLongPrefix( s+1, l );
}
int main(int argc, char** argv)
{
    int i;
    char s[30];
    s[0]=NULL;
    ifstream in( "trie.in" );
    ofstream out( "trie.out" );
    root=new trie;
    while( in>>i>>s )
    {
        switch(i)
        {
            case 0 : root->Add(s); break;
            case 1 : root->Del(s); break;
            case 2 : out<<root->CountWordA(s)<<'\n'; break;
            case 3 : i=0, out<<root->MaxLongPrefix(s, i)<<'\n';
        }
    }
    return (EXIT_SUCCESS);
}