The Times Killer 210, Thurs 25 May

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The Times Killer 210, Thurs 25 May

Postby Crazy Girl » Thu May 25, 2006 10:18 pm

has anyone managed to solve today's Killer, no. 210, in The Times, tried to solve it on paper and hit an inconsistency and thought i made an error but can't see it, have just plugged it in to JC's program and it can't solve the puzzle.

puzzle found at following link:-
http://www.timesonline.co.uk/article/0,,18209-2195406,00.html

:):(
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Postby Ruud » Fri May 26, 2006 2:44 am

Crazy Girl wrote:has anyone managed to solve today's Killer, no. 210, in The Times


Here is the puzzle in PS format:

3x3::k:5888:3073:3073:3073:4613:4613:2575:2575:2575:5888:5888:4619:4619:4613:2071:2575:7697:7697:2834:1820:4619:4619:4613:2071:3096:7697:7697:2834:1820:5156:2590:5663:5663:3096:1827:1827:5156:5156:5156:2590:2590:5663:6955:6955:2860:2879:3119:3119:4919:6193:6193:6955:4916:2860:2879:4919:4919:4919:6193:6193:6955:4916:2860:2879:5440:3147:4677:4677:4677:4677:4916:4916:5440:5440:3147:3147:3918:3918:3918:2128:2128:

I have no problem solving it with SumoCue.

Ruud.
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Postby djape » Fri May 26, 2006 6:32 am

Cathy,

Perfect Sudoku v0.5 (unreleased) rated this IQ, while v0.4 rated it INSANE.

Good to hear they started posting some more difficult puzzles.:)

Cheers,

DJ.
www.djape.net
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Postby Ruud » Fri May 26, 2006 8:38 am

djape wrote:Perfect Sudoku v0.5 (unreleased) rated this IQ, while v0.4 rated it INSANE.

What causes this high rating? I see nothing extremely difficult in this solving path:

45-test N3 -> R4C7=7 -> R3C7=5
45-test N124 -> R6C1=6 -> R2C2=6 -> R12C1={89}
cage 11[2] in N14 = {47} -> R3C1=7,R4C1=4 -> R9C1=5
cage 11[3] in C1 = {623} -> R5C1=1
45-test N12 -> R4C2=3 -> R3C2=4
cage 21[3] in N7 = {579}
Cage 12[2] in N4 = {57} -> R6C2=5, R6C3=7
Digit 7 locked in R2N3
Digit 6 locked in R3N3
cage 8[2] in N2 = {35} R2C6=5, R3C6=3
R1C3=5,R2C3=3
cage 12[3] in N12 = {156} -> R1C2=1, R1C4=6 -> R3C3=2
cage 18[4] in N12 = {2349} -> R2C4=4, R3C4=9 -> R3C5=1
R2C7=1 -> R2C5=2
cage 18[4] in N2 = {1278} -> R1C1=9, R2C1=8
R5C2=2,R7C2=8,R8C4=8,R9C7=8
45-test R9 -> R8C23 = 11 = {74} -> R8C2=7, R8C3=4, R9C2=9
45-test C123 -> R9C4 = (R7C3 + 1) - > R9C4={27}
R9C5=3 -> R9C6=4
45-test N69 -> R8C7=3 -> R8C1=2 -> R7C1=3
cage 18[4] in R8={1368} -> R8C5=6, R8C6=1
naked pair {59} in N9
R1C7=2
45-test C89 -> R5C8=8 -> R3C8=6, R3C9=8
R5C3=9, R4C3=8
cage 22[3] in N5 = {679} -> R4C5=9,R4C6=6,R5C6=7
the rest is singles only

Ruud
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Postby djape » Fri May 26, 2006 9:30 am

Ruud, the reason is your second step - "complex innies/outies". For unexperienced solvers this is not so easy to spot, plus, once you do spot it, you have to add 10 cage sums and subtract 3*45 from it. So there's lots of (simple) arithmetic and it's not an "automatic" operation.

Actually, if I plug-in number 6 in R6C1, PS v0.5 rates this puzzle only THINKER. Perhaps 2 increases in the level of difficulty for one "complex innies/outies" may be too much. So I'd say that BRAIN is about the right estimate of difficulty.

Like I said many times - difficulty levels are there just as a rough description of the puzzle. Realistically it's a very personal thing - Crazy Girl is an experienced solver, yet she had problems with this puzzle.

I find it funny when authors place "solving time" next to a puzzle. If it's there for marketing purposes - Ok, but otherwise it's as good as a random number.
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Postby Bigtone53 » Fri May 26, 2006 10:09 am

I find it funny when authors place "solving time" next to a puzzle. If it's there for marketing purposes - Ok, but otherwise it's as good as a random number.


Killer 211 in today's The Times repeats last Saturday's one, but it has got 5 minutes harder since then!
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Postby Crazy Girl » Fri May 26, 2006 10:14 am

No problem on Killer 210, made a mistake inputting the grid, and got the innes/outties the wrong way round, need to go and screw on a new head:!:
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