The New Sudoku Players' Forum

by **ncantoral** » Mon Aug 25, 2008 2:02 am

Code: Select all: 3 . .|4 . .|. . . . 4 .|. . .|2 . . 8 . .|9 7 .|. 5 . -----+-----+----- . . 1|6 . .|. . . . 5 .|. 9 .|. 6 . . . .|. . 3|8 . . -----+-----+----- . 1 .|. 5 7|. . 6 . . 9|. . .|. 4 . . . .|. . 9|. . 7

Code: Select all: ------------------------------------------------------------------- | 3 9 57 | 4 28 258 | 6 178 18 | | 1 4 57 | 358 36 568 | 2 789 89 | | 8 26 26 | 9 7 1 | 34 5 34 | ----------------------+---------------------+---------------------- | 2479 38 1 | 6 28 2458 | 34579 239 23459 | | 247 5 38 | 278 9 248 | 1347 6 1234 | | 24679 267 246 | 257 1 3 | 8 29 2459 | ----------------------+---------------------+---------------------- | 24 1 2348 | 238 5 7 | 39 2389 6 | | 257 2378 9 | 1238 36 268 | 135 4 12358 | | 256 2368 2368 | 1238 4 9 | 135 1238 7 | -------------------------------------------------------------------

for the solvers again.

by **ttt** » Mon Aug 25, 2008 5:47 am

Hi ncantoral,
I've just posted my solution for this puzzle on there (using AU notation

)

ttt

by **daj95376** » Mon Aug 25, 2008 11:23 am

[Withdrawn: mindless]

by **hobiwan** » Mon Aug 25, 2008 1:46 pm

Picking up at daj95376's first candidate grid:

daj95376 wrote:
Code: Select all
+-----------------------------------------------------------------------+ | 3 9 57 | 4 28 258 | 6 178 18 | | 1 4 57 | 358 36 568 | 2 789 89 | | 8 26 26 | 9 7 1 | 34 5 34 | |-----------------------+-----------------------+-----------------------| | 2479 38 1 | 6 28 2458 | 34579 239 23459 | | 247 5 38 | 278 9 248 | 1347 6 1234 | | 24679 267 246 | 257 1 3 | 8 29 2459 | |-----------------------+-----------------------+-----------------------| | 24 1 2348 | 238 5 7 | 39 2389 6 | | 257 2378 9 | 1238 36 268 | 135 4 12358 | | 256 2368 2368 | 1238 4 9 | 135 1238 7 | +-----------------------------------------------------------------------+

Code: Select all: Forcing Net Verity => r5c4=7 r5c4=2 (r8c6=2 r8c9<>2) (r5c9<>2) r6c4=7 r6c9=5 r4c9=2 (r4c7=4 r4c1<>4) (r4c9<>4) r6c8=9 r4c1=9 r4c7=7 r4c6=4 r6c4=5 r5c4=7 r5c4=7 r5c4=7 r5c4=8 (r8c6=8 r8c9<>8) r1c5=8 (r1c9=1 r5c9<>1) r2c9=8 r2c8=9 (r4c8<>9) r6c8=2 (r5c9<>2) r4c8=3 r5c9=4 r4c6=4 r6c4=5 r5c4=7 Forcing Net Verity => r3c9=3 r5c7=1 (r5c7<>4) r4c7=7 r3c7=4 r3c9=3 r5c9=1 (r5c9<>3) r1c9=8 r4c5=8 r4c2=3 (r4c8<>3) (r4c7<>3) r5c7=3 r3c9=3 Naked Single: r3c7=4 Hidden Single: r4c7=7 Hidden Single: r7c7=9 Locked Candidates Type 1 (Pointing): 5 in b6 => r8c9<>5 Naked Pair: 2,4 in r57c1 => r4689c1<>2, r46c1<>4 Naked Single: r4c1=9 Naked Triple: 3,8,2 in r4c258 => r4c69<>2, r4c6<>8 .------------------.------------------.------------------. | 3 9 57 | 4 28 258 | 6 178 18 | | 1 4 57 | 358 36 568 | 2 789 89 | | 8 26 26 | 9 7 1 | 4 5 3 | :------------------+------------------+------------------: | 9 38 1 | 6 28 45 | 7 23 45 | | 24 5 38 | 7 9 248 | 13 6 124 | | 67 267 246 | 25 1 3 | 8 29 2459 | :------------------+------------------+------------------: | 24 1 2348 | 238 5 7 | 9 238 6 | | 57 2378 9 | 1238 36 268 | 135 4 128 | | 56 2368 2368 | 1238 4 9 | 135 1238 7 | '------------------'------------------'------------------' Almost Locked Set XY-Wing: A=r1c569 - {1258}, B=r4c5,r6c4 - {258}, C=r5c169 - {1248}, Y,Z=1,8, X=5 => r2c4,r4c6<>5 Forcing Chain Verity => r5c9=1 r7c3=3 r5c7=3 r5c9=1 r7c4=3 r2c4=8 r1c5=2 r4c8=2 r5c7=3 r5c9=1 r7c8=3 r5c7=3 r5c9=1 Singles

by **Carcul** » Sun Oct 05, 2008 3:20 pm

Code: Select all: *---------------------------------------------------------------* | 3 9 57 | 4 28 258 | 6 178 18 | | 1 4 57 | 358 36 568 | 2 789 89 | | 8 26 26 | 9 7 1 | 34 5 34 | |--------------------+--------------------+---------------------| | 2479 38 1 | 6 28 2458 | 34579 239 23459 | | 247 5 38 | 278 9 248 | 1347 6 1234 | | 24679 267 246 | 257 1 3 | 8 29 2459 | |--------------------+--------------------+---------------------| | 24 1 2348 | 238 5 7 | 39 2389 6 | | 257 2378 9 | 1238 36 268 | 135 4 12358 | | 256 2368 2368 | 1238 4 9 | 135 1238 7 | *---------------------------------------------------------------*

1) [r5c7]=1=[r5c9]-1-[r1c9]-8-[r1c5]-2-[r4c5]-8-[r4c2]-3-[r4c789]=3=
=[r5c7], => r5c7<>4,7.

2) [r4c9]=5=[r4c6]=4=[r5c6]-4-[r5c79|r46c8]-2,9-[r4c9], => r4c9<>2,9.

3) [r5c4]=7=[r6c4]=5=[r2c4]-5-[r2c3]-7-[r2c8]=7=[r1c8]=1=[r1c9]-1-
-[r5c9]=1=[r5c7]=3=[r4c8]-3-[r4c2]-8-[r4c5]-2-[r56c4], => r5c4, r6c4<>2.

4) [r5c4]=7=[r6c4](=5=[r4c6]=4=[r5c6]-4-[r5c9])=5=[r2c4]=3=[r2c5]
=6=[r2c6]-6-[r8c6]-8-[r58c9]-1-[r1c9]-8-[r1c5]=8=[r4c5]-8-[r5c4], => r5c4<>8.

5) [r8c7]=5=[r9c7]-5-[r9c1]-6-[r6c1]-7-[r6c2]=7|4=[r6c3]-4-[r6c9]=4=
[r5c9]=1=[r5c7](-1-[r8c7])=3=[r5c3]=8=[r5c6]-8-[r8c6]-6-[r8c5]-3-
-[r8c7], => r8c7<>1,3.

6) [r5c7]=1=[r5c9]-1-[r1c9]-8-[r1c5]=8=[r4c5]=2=[r4c8]=3=[r5c7], => r8c9<>1, r1c68<>8.

7) [r7c3]=4=[r6c3]-4-[r6c9]=4=[r5c9]=1=[r5c7]=3=[r9c7]-3-[r9c23]
=3|8=[r9c23]-8-[r7c3], => r7c3<>8.

8) [r9c3]=8=[r5c3]=3=[r5c7]=1=[r5c9]=4=[r6c9]-4-[r6c3]=4=[r7c3]-4-
-[r7c1]-2-[r48c2]-3,8-[r9c2]-2,6-[r9c3], => r9c3<>2,6.

9) BUG: r2c6=8 and the puzzle is solved.

by **susume** » Mon Oct 06, 2008 6:52 am

Carcul,

Sorry if I'm being dense -- in your first Nice Loop, how do you get [r4c789]=3=[r5c7] when there is still a candidate 3 in r5c9?

by **Pat** » Mon Oct 06, 2008 7:02 am

susume wrote:Carcul,

Sorry if I'm being dense -- in your first Nice Loop, how do you get [r4c789]=3=[r5c7] when there is still a candidate 3 in r5c9?

r5c9 became 1 right at the start of the loop

by **daj95376** » Mon Oct 06, 2008 9:21 am

susume wrote:Carcul,

Sorry if I'm being dense -- in your first Nice Loop, how do you get [r4c789]=3=[r5c7] when there is still a candidate 3 in r5c9?

Carcul doesn't announce when he's using a network. He also doesn't announce when he's embedding a UR/DP relationship. It makes his solutions sometimes more challenging than the original puzzle.

The New Sudoku Players' Forum

AU 8-25-2008 tough

AU 8-25-2008 tough