Why havent a example at the discription

waste some time on figure out how to calculate the total avg(array2 -> 4300 ); Lol

The output should have been an optional tuple of an int and a char, not a nullable, necessarily heterogeneous, array. This is overly monolinguistic.

I'm not sure what can be done now. Python ( and, proposed, Haskell ) correctly use a tuple, but the description suffers.

Haskell translation

this translation modifies the description

How you did it 😁

intersting , thanks anthor

2 => 16

😂😂😂😂 crasy

intersting, key is recognise the odd/even

               v                           v   v
expected [ 9, +0, 9, 1, 2, 1, 1, 3, 1, 9, +0, +0, 9, +0, +0, +0, +0, +0, +0, +0 ] to deeply equal 
         [ 9, 9, 1, 2, 1, 1, 3, 1, 9, 9, +0, +0, +0, +0, +0, +0, +0, +0, +0, +0 ]

The first value there is your answer, and you can see there are more than one 0 not at the end. Probably you're mutating the array at the same time you run through it, skipping values.

About what +0 is, you can see that's 0, don't mind the + before it, it's probably chai adding it in the assertion.

I don't understand what is wrong
expected [ 9, +0, 9, 1, 2, 1, 1, 3, 1, 9, +0, +0, 9, +0, +0, +0, +0, +0, +0, +0 ] to deeply equal [ 9, 9, 1, 2, 1, 1, 3, 1, 9, 9, +0, +0, +0, +0, +0, +0, +0, +0, +0, +0 ]

+0 what is this?

lowerCase

counting number of occurrences 1

Actually，it's a easier than 5kyu problem, 7ky is enough

haha