Initial data commit

Task/CUSIP/Haskell/cusip-2.hs

@@ -0,0 +1,37 @@
+import qualified Data.Map as M (Map, fromList, lookup)
+import Data.Maybe (fromMaybe)
+
+-------------------------- CUSIP -------------------------
+
+cusipMap :: M.Map Char Int
+cusipMap =
+  M.fromList $
+    zip (['0' .. '9'] <> ['A' .. 'Z'] <> "*@#") [0 ..]
+
+cusipValid :: String -> Bool
+cusipValid s =
+  let ns = (fromMaybe [] . traverse (`M.lookup` cusipMap)) s
+   in (9 == length ns)
+        && let qrSum =
+                 sum $
+                   ( [quot, rem]
+                       <*> zipWith
+                         id
+                         (cycle [id, (* 2)])
+                         (take 8 ns)
+                   )
+                     <*> [10]
+            in last ns == rem (10 - rem qrSum 10) 10
+
+--------------------------- TEST -------------------------
+main :: IO ()
+main =
+  mapM_
+    (print . ((,) <*> cusipValid))
+    [ "037833100",
+      "17275R102",
+      "38259P508",
+      "594918104",
+      "68389X106",
+      "68389X105"
+    ]