You can SHORT it with : -1 ?l?u?d ?1?1...
l | abcdefghijklmnopqrstuvwxyz
u | ABCDEFGHIJKLMNOPQRSTUVWXYZ
d | 0123456789
If you want to REDUCE the keyspace: remove some characters, for that you need to have some hints about the password
l | abcdefghijklmnopqrstuvwxyz
u | ABCDEFGHIJKLMNOPQRSTUVWXYZ
d | 0123456789
If you want to REDUCE the keyspace: remove some characters, for that you need to have some hints about the password