Thanks for the answer, help me a lot

OP solved it, closing

$ is the reverse list of test answers.
sumStrings pops the end element off it.
It doesn't address the problem in any way.

Any kata where an answer like this is possible is in dire need of randomised tests.

I have a same problem :/

Me too, always.

Your solution is failing for empty string. You can print the string using console.log and you'll see there's nothing where it fails.

Can you tell me how you think "witouth memorization" because the expexted number is nth value in "Hamming" array?

There is copied BigNumber class from declaration, and on bottom just use that.
Kata is something which we should use for interesting study, not for cheating bro.

Can anyone explain this?

This is not solution for problem, this is the cheat for test...

I feel just like you...

I think this is so easy for 5kyu , this kata is for 7kyu :)