Bad. in this map, you need to write an analog of the xor operator and not use it

This is a clever use of exceptions, though I would avoid this in production code. Raising exceptions is costly, and also if "a" happens to be a long string you would be creating a string 50 times larger.

good use!

Thuis a brilliant codewar

I tested functional programming vs a for loop and it seems like the for loop can be about 100ms faster than the functional programming approach. Not too sure why

Added for Python, still missing for JS and Ruby

Approved

python new test framework + random tests are required. updated in this fork

u sure that this is a good option? ty

most readable

It's just how the || operator works in JS.

not quite sure why (0 || null) returns null, not 0.

so pythonic