Initial data commit

Task/Gray-code/Standard-ML/gray-code.ml

@@ -0,0 +1,25 @@
+fun gray_encode b =
+  Word.xorb (b, Word.>> (b, 0w1))
+
+fun gray_decode n =
+  let
+    fun aux (p, n) =
+      if n = 0w0 then p
+      else aux (Word.xorb (p, n), Word.>> (n, 0w1))
+  in
+    aux (n, Word.>> (n, 0w1))
+  end;
+
+val s = Word.fmt StringCvt.BIN;
+fun aux i =
+  if i = 0w32 then
+    ()
+  else
+    let
+      val g = gray_encode i
+      val b = gray_decode g
+    in
+      print (Word.toString i ^ " :\t" ^ s i ^ " => " ^ s g ^ " => " ^ s b ^ "\t: " ^ Word.toString b ^ "\n");
+      aux (i + 0w1)
+    end;
+aux 0w0