haskell problem 22, 24, 25, 29, 39, 40, 45, 53, 59

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diff --git a/haskell/024-lexicographic_premutations.hs b/haskell/024-lexicographic_premutations.hs
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+-- Lexicographic permutations
+--
+-- Problem 24
+-- A permutation is an ordered arrangement of objects. For example, 3124 is one possible
+-- permutation of the digits 1, 2, 3 and 4. If all of the permutations are listed numerically
+-- or alphabetically, we call it lexicographic order. The lexicographic permutations of
+-- 0, 1 and 2 are:
+--
+-- 012   021   102   120   201   210
+--
+-- What is the millionth lexicographic permutation of the digits
+-- 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?
+
+
+import Data.Char(chr,ord)
+
+main = print (foldr (\x acc -> chr (ord '0' + x) : acc) "" ((permutations' [0..9]) !! 999999))
+
+permutations' :: [Int] -> [[Int]]
+permutations' [x] = [[x]]
+permutations' xs = concat [[x : p | p <-  permutations' (filter (x/=) xs)] | x <- xs]