   Date: Sun, 12 May 91 18:01:38 -0400 (EDT)   From: Nichael Cramer <ncramer@bbn.com > ~~~ Subject: ARGGHHH!! [was: 5by cubes]

Date: Sun, 12 May 91 17:12:57 EDT
From: Nichael Cramer <ncramer@BBN.COM>
To: "Dale I. Newfield" <dn1l+@andrew.cmu.edu>
Subject: Re: 5by cubes
>Date: Sat, 11 May 91 03:47:40 -0400 (EDT)
>From: "Dale I. Newfield" <dn1l+@andrew.cmu.edu>
>To: Cube-Lovers@life.ai.mit.edu
>I am only having one problem with the 5x5x5 cube, though:
>X|O|X|X|X
>X|X|X|X|X
>X|X|X|X|X
>X|X|X|X|X
>X|X|X|O|X
>looking at the bottom of my cube, the 2 pieces marked O are swaped
>sometimes, so that the face is still a solid color, but the sides are
>swapped. [ ... ] I can't figure out what causes the swapping.

```[I write]:
>Dale, [...]

#\$%@!!
```

I just realize that I answered the wrong question! My answer was to the
question:

"My cube is completely solved *except* that the 2 pieces marked `O' are
flipped."

(Sorry.) The right answer should be:

The state of the cube is not:

```X|O|X|X|X                  X|A|X|C|X
X|X|X|X|X                  X|X|X|X|X
X|X|X|X|X     But rather:  X|X|X|X|X
X|X|X|X|X                  X|X|X|X|X
X|X|X|O|X                  X|X|X|B|X
```

Where cubie "C" just "looks" like it's in the right place.

You need an operator that rotates A->B->C->A. (Left as an exercise; hints
available on request.)

This will very likely leave an inconvenient number of edges flipped. For
the answer to _this_ problem, see my last post. ;)

Nichael-walks-with-the-red-face     