nickangtc · March 21, 2022 08:23 · Mar 4, 2022 · Mar 4, 2022 · Mar 4, 2022
diff --git a/triangle-koan-ruby.rb b/triangle-koan-ruby.rb
@@ -21,11 +21,9 @@ def validate_triangle(a, b, c)
 # Josh's beautiful solution taken from https://stackoverflow.com/a/14445542/6463816
 # ===
 def triangle(a, b, c)
-  # answers part 2
   [a, b, c].permutation do |sides|
     raise TriangleError unless sides[0] + sides[1] > sides[2]
   end
-  # answers part 1
   case [a,b,c].uniq.size
     when 3; :scalene
     when 2; :isosceles

diff --git a/triangle-koan-ruby.rb b/triangle-koan-ruby.rb
@@ -0,0 +1,37 @@
+# exercise is from http://rubykoans.com/ - a great way to learn ruby!
+
+#! my not so succinct but works solution
+def triangle(a, b, c)
+  validate_triangle(a, b, c)
+  if a == b && b == c
+    :equilateral
+  elsif a != b && b != c && c != a
+    :scalene
+  else
+    :isosceles
+  end
+end
+
+def validate_triangle(a, b, c)
+  raise TriangleError, "No such thing as negative or 0-length sides in a triangle" if a <= 0 || b <= 0 || c <= 0
+  raise TriangleError, "Incomplete triangle because the sides cannot touch and close up" if a + b <= c || a + c <= b || b + c <= a
+end
+
+# ===
+# Josh's beautiful solution taken from https://stackoverflow.com/a/14445542/6463816
+# ===
+def triangle(a, b, c)
+  # answers part 2
+  [a, b, c].permutation do |sides|
+    raise TriangleError unless sides[0] + sides[1] > sides[2]
+  end
+  # answers part 1
+  case [a,b,c].uniq.size
+    when 3; :scalene
+    when 2; :isosceles
+    when 1; :equilateral
+  end
+end
+
+class TriangleError < StandardError
+end