Secret Code Finder

The player has fine grained control over complexity from extremely dummy to insanely hard.
Three types of games:
Single player
Play vs Android (two AI playing algorithms - easy and hard)
Multiplayer (vs random player or vs a friend)

Own code creation, or auto generated code following current code configuration options:

Distinguishable source elements count between: 2 and 9.
Code possitions between: 2 and 6.
Maximum repeating elements in code between: 1 (no repeats) and 9 (current number of elements).
Empty cells: between 0 (disallowed) and 9 (current max repeats).

Not all code configurations are valid. To be valid the following, should be true:

1. (Elements + Empty) x Repetitions >= Code Size.
2. Repetitions <= Code Size

The game prevents you from invalid configuration and will receive message each time, when your configuration is about to become invalid.

Enjoy the game while training your brain!