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17 votes (50%)
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10 votes (29.41%)
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34 members have voted

miplet
miplet 
Joined: Dec 1, 2009
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February 9th, 2021 at 9:57:58 AM permalink
I did that Sudoku when it was featured on Cracking the Cryptic.
“Man Babes” #AxelFabulous
Gialmere
Gialmere
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February 10th, 2021 at 4:21:03 PM permalink

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Police have warned that the Sudoku Killer is still at large and making threats.

He will kill either 1, 4, or 9 people today.
Have you tried 22 tonight? I said 22.
gordonm888
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gordonm888
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February 11th, 2021 at 7:14:39 AM permalink
It would be useful if someone could explain the logic for how to "get the first number" in the Sudoku puzzle. I guessed the middle square must be "5" because of the "magic Square" requirement on the shaded inner grid of 9 boxes, but what then? How do you deduce the next number?
So many better men, a few of them friends, are dead. And a thousand thousand slimy things live on, and so do I.
ThatDonGuy
ThatDonGuy
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February 11th, 2021 at 7:38:08 AM permalink
Quote: gordonm888

It would be useful if someone could explain the logic for how to "get the first number" in the Sudoku puzzle. I guessed the middle square must be "5" because of the "magic Square" requirement on the shaded inner grid of 9 boxes, but what then? How do you deduce the next number?



The possible values of a row in a Magic Square that does not include the number 5 are (1,6,8), (2,4,9), (2,6,7), and (3,4,8).
The top row of the center block cannot contain 3, 4, or 8; that leaves (2,6,7).
The 2 cannot be in the upper left because of the 2 at the bottom right of the grid and the "both main diagonals have nine unique digits" rule.

If the upper right is 7, then the upper left is 6 and the bottom left has to be 3, but then the left column has to be (6, 6, 3).
If the upper right is 6, then the upper left is 7 and the bottom left has to be 4, but then the left column has to be (6, 5, 4).
Therefore, the upper right is 2, and the lower left is 8. This means the upper left cannot be 7, as the left column would be at least 16.
The upper left is 6, so the top row is (6, 7, 2), which means the bottom row is (8, 3, 4) and the middle row is (1, 5, 9).

Gialmere
Gialmere
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February 12th, 2021 at 8:41:40 AM permalink


There are countless chess variations in the world. (Currently, 5D chess with multiverse time-travel is popular.) The game depicted above (more of a study really) is a 1D variant. That is, the board consists of a single row of 8 squares.

The rook and king pieces move as they do in regular chess although obviously restricted to only the forward/back (left/right if you prefer) directions. The knight pieces move 2 spaces in either direction. They jump over any piece on the middle space.

Because of the simplified nature of the the game and because it moves first, White can win every time. White must be careful, however, since a foolish move will result in a stalemate or even a loss.

Assuming both sides use optimal strategy, how many moves will it take White to checkmate the Black king?
Have you tried 22 tonight? I said 22.
charliepatrick
charliepatrick
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February 12th, 2021 at 10:24:59 AM permalink
Quote: Gialmere

...Assuming both sides use optimal strategy, how many moves will it take White to checkmate the Black king?...

If the Rook moves first then Black can either Mate or ensure a draw.
So the (white) Knight moves.
If the (black) rook takes the Knight, then White can ensure a Mate (1) N, rxN (2) Rxr, n (3) Rxn ##
If the (black) knight moves, then White (1) N, n (2) Nxr #, k (3) Rxn, k (4) N ## (K _ R N n r _ k; K _ R _ n N k _; K _ _ _ R N _ k)
If the (black) rook moves, then White moves Knight to check (1) N, r (2) N#, rxN, Rxr results in a stalemate
If the (black) rook moves, then White moves his Rook back and only the black rook can move
(a) rook moves back (1) N, r (2) R, r (3) Nxr ##
(b) rook takes Knight (1) N, r (2) R, rxN (3) Rxr, n (4) Rxn ## (K _ R N r _ n k ; K R _ r _ _ n k; K _ _ R n _ _ k)

So I get that Black can play to delay the mating until White's fourth move.
gordonm888
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gordonm888
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February 12th, 2021 at 4:16:35 PM permalink


The white rook can take the black rook, RxR on f.

1. White: RxR Black: Only move is N jumps rook to space e. placing himself in Mate.

White wins in one move.

So many better men, a few of them friends, are dead. And a thousand thousand slimy things live on, and so do I.
unJon
unJon
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Thanks for this post from:
gordonm888
February 12th, 2021 at 4:19:00 PM permalink
Quote: gordonm888



The white rook can take the black rook, RxR on f.

1. White: RxR Black: Only move is N jumps rook to space e. placing himself in Mate.

White wins in one move.



That would be an illegal move (placing ones one king in check) leaving black with no legal moves so a stalemate.
The race is not always to the swift, nor the battle to the strong; but that is the way to bet.
Gialmere
Gialmere
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February 12th, 2021 at 4:47:06 PM permalink
Quote: charliepatrick

If the Rook moves first then Black can either Mate or ensure a draw.
So the (white) Knight moves.
If the (black) rook takes the Knight, then White can ensure a Mate (1) N, rxN (2) Rxr, n (3) Rxn ##
If the (black) knight moves, then White (1) N, n (2) Nxr #, k (3) Rxn, k (4) N ## (K _ R N n r _ k; K _ R _ n N k _; K _ _ _ R N _ k)
If the (black) rook moves, then White moves Knight to check (1) N, r (2) N#, rxN, Rxr results in a stalemate
If the (black) rook moves, then White moves his Rook back and only the black rook can move
(a) rook moves back (1) N, r (2) R, r (3) Nxr ##
(b) rook takes Knight (1) N, r (2) R, rxN (3) Rxr, n (4) Rxn ## (K _ R N r _ n k ; K R _ r _ _ n k; K _ _ R n _ _ k)

So I get that Black can play to delay the mating until White's fourth move.


Quote: gordonm888



The white rook can take the black rook, RxR on f.

1. White: RxR Black: Only move is N jumps rook to space e. placing himself in Mate.

White wins in one move.



Sorry. All incorrect.
Have you tried 22 tonight? I said 22.
teliot
teliot
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February 13th, 2021 at 6:36:25 AM permalink
Quote: Gialmere


Mate is not possible for white with optimal black strategy, unless I'm missing a rule.

1. Rxr is stalemate.
1. Re1, rxR is stalemate.
1. Rd1, rxR is stalemate.
1. Nd1, rxN, 2. Rxr is stalemate.
1. Nd1, rxN, 2. Rb1, rxR is a draw.
1. Nd1, rxN, 2. Kb1, rxR is a draw.
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