you can print the arguments

I would recommend reading up on higher order functions

Thanks a lot for the reply. Now I understand

4 is not a peak.

            peaks
          v       v
          *  
v         *
a         * *
l   *   * * *     *         *
u   * * * * *   * * *    *  *
e   * * * * * * * * * *  *  *

pos 0 1 2 3 4 5 6 7 8 9 10 11

I have a question. Why does pickPeaks([3, 2, 3, 6, 4, 1, 2, 3, 2, 1, 2, 3]) should return {pos: [3, 7], peaks: [6, 3]}, whereas the 2 peaks of the list are 6 and 4 at the positions 3 and 4. It should've returned {pos: [3, 4]}, peaks: [6, 4]. Am I wrong? Explain me

This kata is really difficult. I have no ideas about it. I could barely print the first function

also, keep up with the spoiler tags ;)

Then please accept my apologies :-) I am kind of new here...

Correct. Maybe BASIC TESTS in 'attempt' mode has more tests than you see in 'test' mode.

Are you saying that the BASIC TESTS when pressing Attemp is not the same as the BASIC TESTS you get when you click Test?

Nothing broken. When you press "Attempt" there are many more tests.