Strange that I got it working and the answer has solid hint is in here (only read this after I got it) I don't understand yet the mathmatical difference.

Indeed. Despite arr is mutated. ;)

Cool!

Approved. Thanks ;-)

Awesome.

Ruby translation kumited -- please checkand approve!

Also, maybe changing the ranking to 6 kyu would be good.

Nice one. Thanks.
I think it's 6kyu.

It was sort(), sure :) Always forget slice() before it.
Sorry, thanks.

Such as sort(), pop(), shift(), reverse()...

Time: 577ms Passed: 105 Failed: 0
Test Results:
 Basic Tests
 It should works for basic tests (5 of 5 Assertions)
Completed in 16ms
 100 Random Tests
 It should works for random tests too. (100 of 100 Assertions)
Completed in 259ms
 Congratulations! You have passed all the tests!

Perhaps you modified the inputs? ;-)

Is it all OK with tests?
I passed all basic tests and 0 random.
All failed with 'Failed!You've modified the argument items', but I didn't do this.

Thanks!

Nice kata. Thank you.

Yes, the description says "sorted by total call durations", so you should sum them all up...

All right, Betty should come before Ray, that conversion was a mistake in my code. But my question still stands, does it expect you to sum up call durations if a person is called more than once?