This comment is hidden because it contains spoiler information about the solution
The negative number issue is now fixed.
There's still a tab issue I forgot to fix, and it's now fixed.
It's not giving neg numbers. Closed
This issue no longer appears. Closed
Yeah, I've got exactly the same problem.
This may be fixed by replacing tabs with spaces on line 7 on tests file
I've got exactly the same problem
The following warning prevents me from submitting my otherwise correct solution:
The test case doesn't consider the list has repeated element.
Like this, combinations 2 [1,1,1,1,1].
QuickCheck tests should not give negative numbers for group size (e.g. combinations -2 [1, 2, 3, 4])
Tests expect [] when inputting 0, but expect  when inputting negative values or values greater than the length of the list.
Yes fitness[i] is the fitness of chromosome[i].
It looks like you are doing this in Ruby. In that case you should use an integer instead of a binary string.
The description states: "What the test will do is generate a random binary string of 35 digits (a random Integer with 35 bits for Ruby)".
So in Ruby we use Integers instead of strings (since we have Integers of arbitrarily large size already).
I updated the solution to sort the lists and the lists of lists.