finish v5

1 files changed, 12 insertions, 0 deletions

diff --git a/46-50/50.hs b/46-50/50.hs
new file mode 100644
index 0000000..0e9c33b
--- /dev/null
+++ b/46-50/50.hs
@@ -0,0 +1,12 @@
+import Data.List (sortBy, insertBy)
+import Data.Ord (comparing)
+
+huffman :: [(Char, Int)] -> [(Char, String)]
+
+huffman l = build $ map (\(a, b) -> ([(a, "")], b)) $ sortBy (comparing snd) l
+    where build [x] = fst x
+          build (x:y:xs) =
+              build $ insertBy
+                        (comparing snd)
+                        ((add x '0') ++ (add y '1'), snd x + snd y) xs
+                            where add e c = (map (\(a, b) -> (a, c:b)) $ fst e)