Giraffe Hunt
(Published on 10. February 2024, 21:13 by ralphwaldo1)
Normal Sudoku rules apply.
Anti-Giraffe: Cells (1,4) apart cannot be the same.
Arrow: the digits on an arrow add up to the digit in the circle
German Whispers: digits separated by a green line differ by at least 5
Dutch Whispers: digits separated by an orange line differ by at least 4
Renban: digits on the purple line form a set of consecutive non-repeating numbers
Kropki dots: digits joined by a black dot are in the ratio 1:2. Digits joined by a white dot differ by 1.
Little killer: the digits on the indicated diagonal sum to the total given next to it.
Digits separated by a V add to 5. Hunt down and eliminate any giraffes (beware: they are well-camouflaged).
N.B. "Giraffe" is the name given in fairy chess problems to the (1,4) counterpart to the knight, as can be seen in the bonus chess problem, which requires you to find the game score up to the position shown after Black's 6th move, in a game in which knights have been replaced by giraffes.
Proof Game 9.0, Knights replaced by Giraffes.
Chess Solution: (select to display)
1.c4 GIa4 2.c5 GIe5 3.c6 GIxf1 4.cxb7 c6 5.bxc8=B Qa5 6.Bxd7+ Kd8 7.Bxc6 Sg5 8.Ba4 Sc4 9.Kf1 Sb8.
The Ba4 is not the original B, so must be the promoted c-pawn. Black must remove the original B with the GIb8, which has two routes it can take. It goes out via a5, waits while the other black men move out of the way of the new Bishop, then returns via c5.
Solution code: Sudoku - Middle row
Comments
on 13. November 2024, 19:40 by ralphwaldo1
Updated chess problem - unfortunately the previous simpler problem was not sound
on 25. October 2024, 22:02 by ralphwaldo1
Updated with sudokupad link by gdc with conflict checking
on 21. April 2024, 08:25 by Silverstep
Most elaborate and cleverly constructed joke I've ever seen on LMD. Criminally underrated. 10/10 would recommend.
on 29. March 2024, 09:16 by juggler
Your fairy chess problem is fascinating! I figured out the bishop's secret right away, but took me a while to find the move sequence. Crazy that there's a unique solution. It reminds me of the brilliant puzzles in "The Chess Mysteries of Sherlock Holmes" by Smullyan.
on 5. March 2024, 01:29 by Ratfinkz
Some really intricate logic in here.... amazing how much the slight stretch of the constraint changes things! Thank you
on 12. February 2024, 17:09 by Geb
The break in to get the first couple of digits is lovely, an elegant trick! I found this quite difficult, but very satisfying once I got it. Excellent work!
on 11. February 2024, 12:21 by ViKingPrime
This would have felt a lot smoother if I could count to four - a Giraffe move (1,4), future solver! NOT a Camel move (1,3).
That said, beautiful puzzle, really clever stuff. If you can look above the forest and get a clear vision (get it?), things should start to gel.
on 11. February 2024, 03:28 by ThePedallingPianist
This is an excellent showcase of the anti-giraffe rule, and a very cool application of it! Scanning is quite the challenge, but once you're used to it, there are some lovely deductions to be discovered. Loved the introductory chess problem too :)
