solve food chain

go/food-chain/food_chain.go

@@ -16,46 +16,6 @@ var verseNumberToStartingAnimal = map[int]string{
 	8: "horse",
 }
 
-func Verse(verseNumber int) string {
-	lines := []string{firstLine(startingAnimal(verseNumber))}
-	lines = append(lines, middleLines(verseNumber)...)
-	lines = append(lines, lastLine(verseNumber))
-	return strings.Join(lines, "\n")
-}
-
-func middleLines(verseNumber int) []string {
-	if verseNumber <= 1 {
-		return []string{}
-	}
-	if verseNumber == 2 {
-		return verseNumberToMiddleLines[verseNumber]
-	}
-	if verseNumber == 3 {
-		lines := verseNumberToMiddleLines[verseNumber]
-		return append(lines, middleLines(verseNumber - 1)[1:]...)
-	}
-	if verseNumber == 4 {
-		lines := verseNumberToMiddleLines[verseNumber]
-		return append(lines, middleLines(verseNumber - 1)[1:]...)
-	}
-	if verseNumber == 5 {
-		lines := verseNumberToMiddleLines[verseNumber]
-		return append(lines, middleLines(verseNumber - 1)[1:]...)
-	}
-	if verseNumber == 6 {
-		lines := verseNumberToMiddleLines[verseNumber]
-		return append(lines, middleLines(verseNumber - 1)[1:]...)
-	}
-	if verseNumber == 7 {
-		lines := verseNumberToMiddleLines[verseNumber]
-		return append(lines, middleLines(verseNumber - 1)[1:]...)
-	}
-	if verseNumber == 8 {
-		return []string{}
-	}
-	panic(fmt.Sprintf("unsupported verseNumber %v", verseNumber))
-}
-
 var verseNumberToMiddleLines = map[int][]string{
 	2: {
 		"It wriggled and jiggled and tickled inside her.",
@@ -65,37 +25,30 @@ var verseNumberToMiddleLines = map[int][]string{
 		"How absurd to swallow a bird!",
 		"She swallowed the bird to catch the spider that wriggled and jiggled and tickled inside her.",
 	},
-	4: []string{
+	4: {
 		"Imagine that, to swallow a cat!",
 		"She swallowed the cat to catch the bird.",
 	},
-	5: []string{
+	5: {
 		"What a hog, to swallow a dog!",
 		"She swallowed the dog to catch the cat.",
 	},
-	6: []string{
+	6: {
 		"Just opened her throat and swallowed a goat!",
 		"She swallowed the goat to catch the dog.",
 	},
-	7: []string{
+	7: {
 		"I don't know how she swallowed a cow!",
 		"She swallowed the cow to catch the goat.",
 	},
 }
 
-func startingAnimal(verseNumber int) string {
-	return verseNumberToStartingAnimal[verseNumber]
-}
-
-func firstLine(animal string) string {
-	return fmt.Sprintf("I know an old lady who swallowed a %v.", animal)
-}
-
-func lastLine(verseNumber int) string {
-	if verseNumber == 8 {
-		return "She's dead, of course!"
-	}
-	return "I don't know why she swallowed the fly. Perhaps she'll die."
+func Verse(verseNumber int) string {
+	lines := []string{}
+	lines = append(lines, firstLine(verseNumber))
+	lines = append(lines, middleLines(verseNumber)...)
+	lines = append(lines, lastLine(verseNumber))
+	return strings.Join(lines, "\n")
 }
 
 func Verses(start, end int) string {
@@ -109,3 +62,30 @@ func Verses(start, end int) string {
 func Song() string {
 	return Verses(1, 8)
 }
+
+func middleLines(verseNumber int) []string {
+	if verseNumber <= 1 || verseNumber == 8 {
+		return []string{}
+	}
+	if verseNumber == 2 {
+		return verseNumberToMiddleLines[verseNumber]
+	}
+	lines := verseNumberToMiddleLines[verseNumber]
+	return append(lines, middleLines(verseNumber - 1)[1:]...)
+}
+
+func firstLine(verseNumber int) string {
+	animal := startingAnimal(verseNumber)
+	return fmt.Sprintf("I know an old lady who swallowed a %v.", animal)
+}
+
+func startingAnimal(verseNumber int) string {
+	return verseNumberToStartingAnimal[verseNumber]
+}
+
+func lastLine(verseNumber int) string {
+	if verseNumber == 8 {
+		return "She's dead, of course!"
+	}
+	return "I don't know why she swallowed the fly. Perhaps she'll die."
+}