Add comments for crystal analyzer 1.3

analyzer-comments/crystal/darts/hypot.md

@@ -0,0 +1,14 @@
+# Pow
+
+Using `pow`, `sqrt` or `**` is totally valid and can be necessary in many situations.
+However when we want a distance in Cartesian space we can use the [`hypot` method][hypot] which returns the hypotenuse of a right angle triangle with sides x and y.
+
+```crystal
+# Rather than:
+Math.sqrt(number ** 2 + another_number ** 2)
+
+# Consider:
+Math.hypot(number, another_number)
+```
+
+[hypot]: https://crystal-lang.org/api/Math.html#hypot%28value1%2Cvalue2%29-instance-method

analyzer-comments/crystal/darts/uses_hypot.md

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+# Uses the hypot method
+
+Congratulations, your solution uses the hypot method!
+
+Your solution uses an efficient way of calculating the distance from the center of a dartboard and that's worth taking a moment to celebrate.

analyzer-comments/crystal/sieve/do_not_use_div_rem.md

@@ -3,7 +3,7 @@
 Like the instructions mention, the purpose of this exercise is to build a Sieve of Eratosthenes without the use of operations such as division or modulo division.
 Please refer to the [Wikipedia link][wikipedia] for a description of the algorithm.
 
-Building the Sieve of Eratosthenes in an immutable language such as Crystal may feel a bit unnatural,
+Building the Sieve of Eratosthenes without operations such as division or modulo division can be tricky.
 but it is a beautiful algorithm invented more than two millennia ago that is worth learning and implementing.
 
 [wikipedia]: https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes

analyzer-comments/crystal/weighing-machine/missing_method.md

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+# Missing %{method_name} method call
+
+Like the instructions mention, the purpose of this exercise is to learn about getters and setters.
+Manually defining these methods is not inherently bad, but can lead to code which is more verbose and harder to maintain.