Family Day update

Task/Gray-code/Lobster/gray-code.lobster

@@ -0,0 +1,19 @@
+def grey_encode(n) -> int:
+    return n ^ (n >> 1)
+
+def grey_decode(n) -> int:
+    var p = n
+    n = n >> 1
+    while n != 0:
+        p = p ^ n
+        n = n >> 1
+    return p
+
+for(32) i:
+    let g = grey_encode(i)
+    let b = grey_decode(g)
+    print(number_to_string(i, 10, 2) + " : " +
+          number_to_string(i,  2, 5) + " ⇾ " +
+          number_to_string(g,  2, 5) + " ⇾ " +
+          number_to_string(b,  2, 5) + " : " +
+          number_to_string(b, 10, 2))