Wednesday, March 9, 2022

Puzzle Of A Year! – 20-22

20-22 by Stéphane Chomine (22 side)

20-22 is a level 22.02 puzzle announced on Twosday, 22.02.2022, by PuzzleWillBePlayed (PWBP).   It was designed by Stéphane Chomine and consists of 2 pieces that fit within a frame.  When solved, one side shows the numerals 20 and the other 22.

20-22 by Stéphane Chomine (20 side)
I always check out the new puzzles released on PWBP and this one caught my eye and interest.  I quickly printed a copy with a gray frame and red pieces.  One piece has a 2 on each side and the other has a 2 on one side and a 0 on the other.  Of course, the frame has some internal obstructions keeping the pieces from simply sliding in.  Must be a puzzle.

This puzzle embodies several qualities that facilitate the solving process.  The first is the level.   At 22 moves, you would expect it to be non-trivial but not too hard.  The second is that the piece with a 2 on each side is the same when you rotate it 180 degrees on any axis.  That means that you can’t possibly add this piece incorrectly.  You just need to figure out which side of the frame it belongs to.  Lastly, since the piece with the 0 can go in the frame in four different ways, there are only 4 assemblies to check.  With a little experimentation, the complete pas de deux is revealed as the pieces find their final resting place.

20-22 Pieces

A special thanks to all the MPD’rs that unknowingly contributed to this post.


  1. And here I thought I had noticed all the twos.
    Everything but the TWOSDAY.
    That is doubly clever.

    1. Just between the two of us, that's one I got from the MPD.