it asks the result to be sorted in lexicographically order.

I tried your solution which is wrong.

Test Failed
expected: "arp,live,strong"
     got: "live,arp,strong"

I am afraid you didn't correctly read the description. Cheers.

input ? output? assertion message? Without that only one thing can be done here: resolve the issue.

=> ?

BASH

I execute the code correctly and get them into an array but in a different order from the tests. Exactly, the order specified in the instructions :/