Bulls and Cows

Discover the hidden code!
Click, or use arrow keys, to change your guess in each box.
(Bulls and Cows is similar to, but came before, the board game MastermindTM*)
Bulls = correct code, correct position.
Cows = correct code, wrong position.

Try different codes and use your brain to figure it out. (* Note: MastermindTM is a trademark of Pressman Toy Corporation, in no way associated with this website.)