A simple terminal based bulls-and-cows game

How to play it

1. Enter the length of the secret code to be guessed (max. 36).
2. Enter the number of distinct symbols to be used for generating the secret code (max. 36).
   It starts with numbers 0-9. If you want more it continues with lower letters from a-z.
   

8: numbers [0-8] will be used
12: numbers [0-9] and letters [a-c] will be used

3. Enter your guesses until your guess is correct.
   

bull: symbol exist within secret code and position is correct
cow: symbol exist within secret code but position is not correct