initial commit

lab01/fizzbuzz.hs

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+-- Do the game fizzbuzz (http://en.wikipedia.org/wiki/Fizz_buzz).
+-- Return a string counting from 1 to the specified number.
+-- Replace numbers dvisible by 3 with "fizz" and numbers divisible
+-- by 5 with "buzz".  If a number is divisible by both 3 and 5,
+-- replace it with "fizzbuzz".
+
+fb :: Int -> String
+fb x | mod x 3 == 0 && mod x 5 == 0 = "fizzbuzz"
+fb x | mod x 3 == 0 = "fizz"
+fb x | mod x 5 == 0 = "buzz"
+fb x = show x
+
+fizzbuzz :: Int -> String
+fizzbuzz n
+	| n < 0 = error "Non-negative numbers only"
+	| otherwise = unwords $ map fb [1..n]
+
+main :: IO ()
+main = do
+  print (fizzbuzz 1)
+  print (fizzbuzz 7)
+  print $ fizzbuzz 99
+  print $ fizzbuzz 0
+  print $ fizzbuzz (-2)