My C# solution passes 'BasicTest' and 'DoubleTest' but fails on 'Random Tests.' It would be nice to have a broader description.

In order to use Math, you need to import System with using System or use a fully qualified name System.Math.

The C# apparently can not use Math.Abs, it should be able to.
I tested my current code code in Visual studio, with the test cases and it works.

Approved

python new test framework is required. updated in this fork

Wow, thanks! That explains it.

The problem is rather that the way the perfs are measured is biased ("like usual"...?)

Considering the inputs used, the VERY GREAT MAJORITY of the outputs are -1. That means that what is measured is actually:

• v1:
  • call + arithmetic
  • compare
  • return
• v2:
  • call
  • store
  • load + arithmetic
  • compare
  • return

So, yeah, v2 is ofc a tiny bit slower.

Now, if you try with a perfect square as input for each call, the result will be the opposite:

1st variant: 2.9085514545440674
2nd variant: 2.345383644104004

I know that this is old, but why is it slower? Does the assignment really add more time than recalculating the sqrt?

Approved some time ago

Ruby 3.0 should be enabled.

Maybe add a test for [1,1,-1,-1, ... random !=0 ...] (Ruby)?
Several solutions should fail.

This calulates sqrt(sq) twice. Is it more efficient to let s = sqrt(sq) and then use s?

Hi. It was said

Return None if it is not possible to define only one of such values.

I have no idea how to specify this case by another way :)