wip directory for each language

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diff --git a/haskell/wip/021-amicable_numbers.hs b/haskell/wip/021-amicable_numbers.hs
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+-- Amicable numbers
+--
+-- Problem 21
+-- Let d(n) be defined as the sum of proper divisors of n
+-- (numbers less than n which divide evenly into n).
+-- If d(a) = b and d(b) = a, where a ≠ b, then a and b are an amicable
+-- pair and each of a and b are called amicable numbers.
+--
+-- For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 and 110;
+-- therefore d(220) = 284. The proper divisors of 284 are 1, 2, 4, 71 and 142; so d(284) = 220.
+--
+-- Evaluate the sum of all the amicable numbers under 10000.
+
+
+-- 5s isnt pretty, divSum is probably the root of evil
+main = print (sum $ map fst (filterAmicable [2..10000]))
+
+filterAmicable :: [Int] -> [(Int, Int)]
+filterAmicable xs = filter (\(n, s) -> n /= s && any ((==)(s, n)) sums) sums
+    where sums = [(x, divSum x) | x <- xs]
+
+divSum :: Int -> Int
+divSum n = factorise 2
+    where factorise d
+            | d > nSqrt = 1
+            | rest == 0 && d /= quotient = d + quotient + factorise (d + 1)
+            | rest == 0 && d == quotient = quotient + factorise (d + 1)
+            | otherwise = factorise (d + 1)
+            where quotient = n `div` d
+                  rest = n `mod` d
+          nSqrt = floor $ sqrt $ fromIntegral n