Add Modular Arithmetic approach to RaindropConverter

[habere-et-dispertire]

Pull Request

This looks a little more visual in raku with multi-dispatch supporting built-in types:

multi fizz-buzz ( 1) { <                   > }
multi fizz-buzz (36) { < Pling             > }
multi fizz-buzz (85) { <       Plang       > }
multi fizz-buzz (91) { <             Plong > }
multi fizz-buzz (15) { < Pling Plang       > }
multi fizz-buzz (21) { < Pling       Plong > }
multi fizz-buzz (70) { <       Plang Plong > }
multi fizz-buzz ( 0) { < Pling Plang Plong > }

sub raindrop ($heard) {

    [~] fizz-buzz $heard¹² mod 105 or ~$heard

}

I think it's a fun way to explore deeper into a generalized mathematical approach since it shows that this approach works also with a change in factors so long as they remain co-prime.

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Reviewer Resources:

Track Policies

[kahgoh]

Formatting

Suggested change

	import java.math.BigInteger;
	import java.math.BigInteger;

[kahgoh]

The linked page describes the problem differently. It might be confusing because the page starts with "Fizz Buzz" instead and then generalizes the problem - it doesn't describe it in the same terms as the exercise. I think it might help to state the that the problem is like "Fizz" & "Buzz" and that the Modular arithmetic approach can be used to solve this type of problem.

[kahgoh]

Is the default always 0? I was thinking it might be better practice to use case (0) and use default for 1 as that would align more with the instructions.

Also, have you considered using switch expression? The solution would be a bit more compact

return switch ( valueOf(n).modPow( valueOf(12), valueOf(105) ).intValue() ) {
  case 36 -> "Pling";
  case 85 -> "Plang";
  // ... etc ...
}