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Someone has fiddled with my Rubik's cube and messed it up only very minorly. Exactly 3 minicubes are out of place: the up-front, up-back, and down-front edge minicubes need to be cycled round. I remember having learnt a simple way to do this cycle, but can't remember what it is!

Can anyone help me with this?

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First, turn the cube so that the edges are in the UL, UR, and DR positions (upper-left, upper-right, down-right). Then, execute this:

F B' R2 F' B U2

Make sure when you do this that F and B' rotate the two faces in the same direction if you're looking at the cube from the front.

If it didn't work the first time, do it again and it should be solved.


Here's a brief explanation of why this works. The algorithm performs a couple swaps on pairs of edges. You have the upper front row of three pieces, and the upper back row. The first two moves (F B') move them next to two edges which need swapping. Then, R2 swaps the two rows as well as the UR and DR edge.

F' B then moves the two swapped sets back, and U2 swaps the two sets as well as the UL and UR edges.

All in all, this algorithm moves UR to DR, DR to UL, and UL to UR. Since there are two unsolved positions, if you didn't solve it the first time, you can just execute it again and it will take you to the solved position.

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  • $\begingroup$ Does "F B" mean they're both rotated 90 degrees in the same direction, or both clockwise when looking from outside the cube (i.e. in opposite directions)? $\endgroup$ – Rand al'Thor Mar 8 '15 at 12:05
  • $\begingroup$ @rand That's what I get for staying up 'till 5 in the morning. Fixed that notational blip; sorry 'bout that. And glad it helped! $\endgroup$ – Aza Mar 8 '15 at 12:09

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