#include <bits/stdc++.h>
#define CH (*s- 'a')
using namespace std;
struct Trie
{
    int nrfii,cnt;
    Trie *fiu[32];
};
Trie *T=new Trie;
void ins(Trie *nod, char *s)
{
    if(*s=='\n')
    {
        nod->cnt++;    //la capatul cuv, il pune in trie
        return;
    }
    if(nod->fiu[CH]==0)//daca nu avem ramura cu litera din cuv in trie, o creem
    {
        nod->fiu[CH]=new Trie;
        nod->nrfii++;
    }
    ins(nod->fiu[CH],s+1);
}
int del(Trie *nod, char *s)//opusul lui ins; este int/bool pentru a vedea daca se sterge un nod din trie sau nu
{
    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()
{
    int main()
    {
        char line[ 32 ];

        f.getline(line,32);
        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;
    }
    return 0;
}