Works, but not 100% correct. The number at the current index is always added to the left and right sum. By definition, the number at the current index should not be taken into account:

"...
Last one:
You are given the array {20,10,-80,10,10,15,35}
At index 0 the left side is {}
The right side is {10,-80,10,10,15,35}
They both are equal to 0 when added. (Empty arrays are equal to 0 in this problem)
Index 0 is the place where the left side and right side are equal.
...
"

Here, left and right sum are 20 at index 0.

Beautiful

'A'.ord has a value of 65 and if you subtract 64 it will be 1

just WOW!

Aaaaaaaaaah, it's a progression. Aaaaaaaaaah… indeed, this is better than (1..num).sum, cuz if num == 1e36, then we're in trouble. Good stuff! Thanks!

Beautiful

Nice

bruhhh

It is a hard to read one-liner, why is it voted as "best practice"?

Гений

Wouldn't this be the best to put in your code if you need to calculate that ?

This is the fastest and best solution.

poetic

Ooh! I haven't seen each_cons. I like that.