I have the same doubt! Is it a typo or am I missing something?

UPD: I think it should be 2^(i+1)-1.

you can check this out!

You know you are an addict when your rating keeps on decreasing but you still participate and practice :)

A bad round for me :( Problem A consumed too much of time, got two hacks! I hate Problem A :(

Can someone explain C in more detail?

Hope to see some good problems this time! The last week of code wasn't up to the mark.

Recently the standard of questions in hackerrank have been going down. Hope to see a positive trend change. :)

Can someone explain the dp solution of the second problem(max even subarray).

Thanks