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Your task is to set up a symmetrical (both vertically and horizontally) position on the first 7 ranks of a chess board that meet all of the criteria below.

For this puzzle, there is no eighth rank. It does not even exist.

That makes a chess board with 7 ranks x 8 files = 56 squares.

You have only the following pieces and must use all 52 of them:
White:
8 kings, 8 rooks, 4 bishops
Black:
20 kings, 4 rooks, 8 bishops

The pieces must be placed on the 7 x 8 chess board such that all of the following criteria are met:

  1. No king is in check.
  2. No piece has any legal moves.
  3. The position has horizontal and vertical symmetry (by both colors and pieces).

In other words, rearrange the pieces in the setup at this link to meet all of the criteria above. (Example image below)
Note: You don't have to use the link. You can use any other board or website, of course. The link is just one quick, easy option.

FEN:
8/KKRRRRKK/KKB2BKK/RR1BB1RR/krbbbbrk/kkkbbkkk/kkkrrkkk/kkkbbkkk w - - 0 1

enter image description here

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1 Answer 1

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All a matter of getting your pins right:

enter image description here

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    $\begingroup$ Nicely done! Yes it is a complex pin problem. $\endgroup$
    – JLee
    Commented Jun 25, 2022 at 18:49
  • $\begingroup$ I haven't thought about it (just see the question now), but is the solution unique? $\endgroup$
    – WhatsUp
    Commented Jun 26, 2022 at 0:40
  • $\begingroup$ @WhatsUp With the symmetry constraint it may well be but I don't know for sure. $\endgroup$
    – loopy walt
    Commented Jun 26, 2022 at 2:33
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    $\begingroup$ @WhatsUp I wondered the same thing and like Loopy Walt I thought it might be, but I will make you a deal: If you find another position that meets all the requirements, I will throw you 100 rep points. $\endgroup$
    – JLee
    Commented Jun 26, 2022 at 10:05

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