This kata becomes the longest I've taken to solve. (So far). Maybe the kata could have been given a better description to avoid having to go back and forth with the test results and having to guess some "new" test cases which were not mentioned in the description. Maybe it was intentional, and I truly enjoyed solving this kata as it truly made it a challenge for me.

If you added non-random tests for invalid array elements with exactly one invalid element, one test for each position, it would invalidate my first (actually invalid) C solution. That passed but will still fail, only randomly on some random tests because I failed to check the validity of only the first array element.

C translation is horrible in that it doesn't show expected and actual values

I think the question or atleast the test cases should give more clarity/information about the task.

C, C++ and Java translations available. Please review.

Prolog translation kumited. (author inactive)