A-M baby

Task/Gray-code/Perl/gray-code.pl

@@ -0,0 +1,20 @@
+sub bin2gray
+{
+    return $_[0] ^ ($_[0] >> 1);
+}
+
+sub gray2bin
+{
+    my ($num)= @_;
+    my $bin= $num;
+    while( $num >>= 1 ) {
+        # a bit ends up flipped iff an odd number of bits to its left is set.
+        $bin ^= $num;   # different from the suggested algorithm;
+    }                   # avoids using bit mask and explicit bittery
+    return $bin;
+}
+
+for (0..31) {
+    my $gr= bin2gray($_);
+    printf "%d\t%b\t%b\t%b\n", $_, $_, $gr, gray2bin($gr);
+}