From b251ab53893e59f77205203379f48f86827c9ca4 Mon Sep 17 00:00:00 2001
From: chirvasitua <stuart-little@users.noreply.github.com>
Date: Wed, 13 Jan 2021 00:26:31 -0500
Subject: 1st commit on 059_haskell

---
 challenge-059/stuart-little/haskell/ch-2.hs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100755 challenge-059/stuart-little/haskell/ch-2.hs

(limited to 'challenge-059/stuart-little/haskell/ch-2.hs')

diff --git a/challenge-059/stuart-little/haskell/ch-2.hs b/challenge-059/stuart-little/haskell/ch-2.hs
new file mode 100755
index 0000000000..1269923da7
--- /dev/null
+++ b/challenge-059/stuart-little/haskell/ch-2.hs
@@ -0,0 +1,17 @@
+#!/usr/bin/env runghc
+
+-- run <script> <space-separated numbers>
+
+import System.Environment (getArgs,)
+import Control.Monad (liftM,)
+import Data.Digits (digitsRev,)
+import Data.List (transpose,)
+import Data.List.Utils (countElem,)
+
+diffs :: Int -> [Int] -> Int
+diffs l xs = let (zeros,ones,lxs) = (countElem 0 xs,countElem 1 xs,length xs) in
+      div (l*(l-1) - ones*(ones - 1) - (zeros + l - lxs)*(zeros+l - lxs - 1)) 2
+
+main = do
+  nrs <- liftM (map (read::String->Int)) getArgs
+  print $ sum $ map (diffs $ length nrs) $ transpose $ map (digitsRev 2) nrs
-- 
cgit