What is challenging??? I mean the challenge....

Answer 1

Just want to mention they *could* help in job interviews if that is one of your goals. And there are many internet (pages and you tube videos) resources on interview questions and coding interviews. You can also review and vote for the challenge questions to get and idea of what some of these questions used for challenges. Either way studying those questions and understanding the "whys" can help you with your continued learning progression.

Answer 2

https://www.sololearn.com/Discuss/472481/what-are-challenges-in-sololearn-how-it-works

Answer 3

try it,i bet you wouldn't regret