Data commit

Task/Gray-code/Picat/gray-code.picat

@@ -0,0 +1,26 @@
+go =>
+   foreach(I in 0..2**5-1)
+      G = gray_encode1(I),
+      E = gray_decode1(G),
+      printf("%2d %6w %2d %6w %6w %2d\n",I,I.to_binary_string,
+                                         G, G.to_binary_string,
+                                         E.to_binary_string, E)
+   end,
+   nl,
+   println("Checking 2**1300:"),
+   N2=2**1300,
+   G2=gray_encode1(N2),
+   E2=gray_decode1(G2),
+   % println(g2=G2),
+   % println(e2=E2),
+   println(check=cond(N2==E2,same,not_same)),
+   nl.
+
+gray_encode1(N) = N ^ (N >> 1).
+gray_decode1(N) = P =>
+    P = N,
+    N := N >> 1,
+    while (N != 0)
+      P := P ^ N,
+      N := N >> 1
+    end.