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Task/Gray-code/Phix/gray-code.phix

@@ -0,0 +1,21 @@
+function gray_encode(integer n)
+    return xor_bits(n,floor(n/2))
+end function
+
+function gray_decode(integer n)
+integer r = 0
+    while n>0 do
+        r = xor_bits(r,n)
+        n = floor(n/2)
+    end while
+    return r
+end function
+
+integer e,d
+puts(1," N  Binary Gray   Decoded\n"&
+       "==  =====  =====  =======\n")
+for i=0 to 31 do
+    e = gray_encode(i)
+    d = gray_decode(e)
+    printf(1,"%2d  %05b  %05b  %2d\n",{i,i,e,d})
+end for