Great kata, maybe try to mention the rules of (+ - + -) when having a chain of determinates in the details.

Quite a challenging kata, well done.

Question might be a bit idiotic, But I dont understand how to correlate the input with the Allele. Why is Bb ----> B, b while AbCd ----> AC,Ad,bC,bD. What would happen if I had for example 8 digits? QwErTyUi -----> QETU, QETi, QETy etc etc??? Is it just the input/2 in every combination