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Posers and Puzzles

Posers and Puzzles

  1. Subscriber BigDoggProblem
    The Advanced Mind
    11 Dec '06 22:42


    Find the three unoccupied squares on the board that a Black King can not legally occupy.
  2. Standard member cadwah
    ¯\_(^.^)_/¯
    11 Dec '06 22:52 / 1 edit
    Originally posted by BigDoggProblem
    [fen]KR6/R7/8/4PP2/2pP2Pp/2P2B2/3B2Q1/4N3[/fen]

    Find the three [b]unoccupied
    squares on the board that a Black King can not legally occupy.[/b]
    b4, b7, h5 and h1???

    After a bit more thought I have concluded that I don't know how to solve this
  3. Subscriber BigDoggProblem
    The Advanced Mind
    11 Dec '06 23:25 / 2 edits
    Originally posted by cadwah
    b4, b7, h5 and h1???

    After a bit more thought I have concluded that I don't know how to solve this
    You are close to the right answer. Two of the four squares you listed are legal squares; the other two are not.
  4. Subscriber sonhouse
    Fast and Curious
    12 Dec '06 05:37
    Originally posted by BigDoggProblem
    [fen]KR6/R7/8/4PP2/2pP2Pp/2P2B2/3B2Q1/4N3[/fen]

    Find the three [b]unoccupied
    squares on the board that a Black King can not legally occupy.[/b]
    don't see how the black king could be put on any of the 25 squares covered by the rooks for instance, so how can there be just 3?
    Even if the board was upside down, the king couldn't occupy any of those squares so what gives?
  5. Subscriber BigDoggProblem
    The Advanced Mind
    12 Dec '06 05:44
    Originally posted by sonhouse
    don't see how the black king could be put on any of the 25 squares covered by the rooks for instance, so how can there be just 3?
    Even if the board was upside down, the king couldn't occupy any of those squares so what gives?
    Checkmate is legal.
  6. Standard member XanthosNZ
    Cancerous Bus Crash
    12 Dec '06 08:57 / 1 edit
    b7 (adjacent to king) and b4 (impossible double check) are easy.
    The final one is g5 as the checking bishop can't have moved to give check and a discovered check isn't possible (only a pawn on f4 could have interceded but that pawn would have been giving check).

    As for the last move for the other answers given:
    bK@h1:
    0. Qf2(g3)xg2#

    bK@h5:
    0. hxg4+

    The trick is to see what white's last move must have been. An instructive retrograde as always Bigdogg.
  7. 12 Dec '06 09:31
    b4, b7, e2
  8. 12 Dec '06 10:08
    what about f4 and e3 ?
  9. 12 Dec '06 10:20 / 2 edits
    f4 and e3 are possible - in both cases white's last move was a capture by the checking bishop.
  10. Standard member XanthosNZ
    Cancerous Bus Crash
    12 Dec '06 10:31
    Originally posted by David113
    f4 and e3 are possible - in both cases white's last move was a capture by the checking bishop.
    Ah missed that.
  11. Subscriber BigDoggProblem
    The Advanced Mind
    12 Dec '06 16:13
    Originally posted by David113
    b4, b7, e2
    This is the answer the judges were looking for.
  12. 15 Dec '06 09:11
    Originally posted by David113
    b4, b7, e2
    ahh yes the king cannot be on a square where it would have been in check from 2 different pieces (that wasn't part of a discovered check move)
  13. 16 Dec '06 02:34
    also h1
  14. Subscriber BigDoggProblem
    The Advanced Mind
    16 Dec '06 03:04
    Originally posted by bjpcomet
    also h1
    Nope. (Why?)
  15. Standard member XanthosNZ
    Cancerous Bus Crash
    17 Dec '06 08:31
    Originally posted by BigDoggProblem
    Nope. (Why?)
    0. Qf2(g3)xg2#