Data commit

Task/Heronian-triangles/Smalltalk/heronian-triangles.st

@@ -0,0 +1,41 @@
+perimeter := [:triangle | triangle reduce: #+].
+
+squaredArea := [:triangle |
+	| s  |
+	s := (perimeter value: triangle) / 2.
+	triangle inject: s into: [:a2 :edge | s - edge * a2]].
+
+isPrimitive := [:triangle | (triangle reduce: #gcd:) = 1].
+
+isHeronian := [:triangle | (squaredArea value: triangle) sqrt isInteger].
+
+heroGenerator := Generator on: [:generator |
+	1 to: 200 do: [:a |
+	a to: 200 do: [:b |
+	b to: (a+b-1 min: 200) do: [:c |
+		| triangle |
+		triangle := {a. b. c.}.
+		((isPrimitive value: triangle) and: [isHeronian value: triangle])
+			ifTrue: [generator nextPut: triangle]]]]].
+
+heronians := heroGenerator contents.
+sorter := squaredArea ascending , perimeter ascending , #third ascending , #second ascending , #first ascending.
+sorted := heronians sorted: sorter.
+area210 := sorted select: [:triangle | (squaredArea value: triangle) = 210 squared].
+
+header := [:title |
+	Transcript cr; cr; nextPutAll: title; cr.
+	#(peri area a b c) do: [:s | Transcript nextPutAll: s; tab]].
+tabulate := [:t |
+	Transcript cr.
+	Transcript print: (perimeter value: t); tab.
+	Transcript print: (squaredArea value: t) sqrt.
+	t do: [:edge | Transcript tab; print: edge].].
+
+Transcript cr; print: heronians size; nextPutAll: ' heronians triangles of side <= 200 where found'.
+header value: 'first 10 sorted by area, then perimeter, the largest side'.
+(sorted first: 10) do: tabulate.
+header value: 'heronians of area 210'.
+area210 do: tabulate.
+
+Transcript flush.