> The unscrambling problem being solved here is much harder than a typical unscrambling problem, because we are rearranging single columns of pixels. As a conse

> The unscrambling problem being solved here is much harder than a typical unscrambling problem, because we are rearranging single columns of pixels. As a consequence of this design, it is impossible to resolve the horizontal reflection symmetry ambiguity – every image has exactly the same energy score as its mirror image. > In a more typical problem, the image would be sliced into groups of columns, where each group moves as a unit. This situation would reduce the number of pieces to unscramble, and also make the arrangement be unambiguous to horizontal flips.