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+-- Dice Game
+--
+-- Problem 205
+-- Peter has nine four-sided (pyramidal) dice, each with faces numbered 1, 2, 3, 4.
+-- Colin has six six-sided (cubic) dice, each with faces numbered 1, 2, 3, 4, 5, 6.
+--
+-- Peter and Colin roll their dice and compare totals: the highest total wins. The
+-- result is a draw if the totals are equal.
+--
+-- What is the probability that Pyramidal Pete beats Cubic Colin? Give your answer
+-- rounded to seven decimal places in the form 0.abcdefg
+
+
+import System.Random
+import Data.List
+
+main = do
+    gen <- getStdGen
+    let n = 20000
+        peter = map sum $ splitIndex 9 $ randN (1, 4) gen (9 * n)
+        colin = map sum $ splitIndex 6 $ randN (1, 6) gen (6 * n)
+    let score = length $ filter (\(p, c) -> p > c) (zip peter colin)
+    print ((fromIntegral score) / (fromIntegral n))
+
+splitIndex :: Int -> [Int] -> [[Int]]
+splitIndex n xs
+    | length xs < n = []
+    | otherwise = h : splitIndex n t
+    where (h, t) = splitAt n xs
+
+randN :: (Int, Int) -> StdGen -> Int -> [Int]
+randN _ _ 0 = []
+randN r gen n = fst next : randN r (snd next) (n - 1)
+    where next = randomR r gen :: (Int, StdGen)
+