Sudoku Players' Forum (clone)

by **Gee** » Sat Jun 16, 2007 2:21 pm

Code: Select all: [code]I am new to these forums so I hope someone can help me a problem that has vexed me. I am filtering on "6's" using colors. I made r2c7 Blue and r2c9 green. Then I colored r5c7 green and r5c8 Blue. Column 7 now contained both a blue and green cell so I thought that I could exclude a "6" from r7c7. That didn't work and to my surprise, it turned the "6" in c7 was in r7c7. What mistake an I making????? Thanks. [code]*--------------------------------------------------------------------* | 3 25 1 | 9 25 6 | 8 4 7 | | 2489 289 7 | 1348 1238 13 | 126 5 1369 | | 2489 6 24589 | 13478 12358 57 | 12 239 139 | |----------------------+----------------------+----------------------| | 6 1237 234 | 5 9 8 | 17 3 134 | | 5 89 489 | 13 7 13 | 46 689 2 | | 1789 13789 389 | 6 4 2 | 157 389 1359 | |----------------------+----------------------+----------------------| | 178 3578 358 | 1378 13568 9 | 2456 26 456 | | 278 4 2358 | 378 3568 57 | 9 1 56 | | 19 159 6 | 2 15 4 | 3 7 8 | *--------------------------------------------------------------------*

by **MCC** » Sat Jun 16, 2007 2:34 pm

Just to make things a bit clearer.

Gee wrote:I am new to these forums so I hope someone can help me a problem that has vexed me.

I am filtering on "6's" using colors. I made r2c7 Blue and r2c9 green. Then I colored r5c7 green and r5c8 Blue.

Column 7 now contained both a blue and green cell so I thought that I could exclude a "6" from r7c7. That didn't work and to my surprise, it turned the "6" in c7 was in r7c7. What mistake an I making????? Thanks.

Code: Select all
*--------------------------------------------------------------------* | 3 25 1 | 9 25 6 | 8 4 7 | | 2489 289 7 | 1348 1238 13 | 126 5 1369 | | 2489 6 24589 | 13478 12358 57 | 12 239 139 | |----------------------+----------------------+----------------------| | 6 1237 234 | 5 9 8 | 17 3 134 | | 5 89 489 | 13 7 13 | 46 689 2 | | 1789 13789 389 | 6 4 2 | 157 389 1359 | |----------------------+----------------------+----------------------| | 178 3578 358 | 1378 13568 9 | 2456 26 456 | | 278 4 2358 | 378 3568 57 | 9 1 56 | | 19 159 6 | 2 15 4 | 3 7 8 | *--------------------------------------------------------------------*

by ab » Sat Jun 16, 2007 2:35 pm

You can colour the 6s in row 2 as there are only 2 of them. However you can't continue this colouring as there are more than 2 6s in column 7 and in column 9. The 6s in row 5 should be different colours. If the ones in row 2 are blue and green, use red and yellow for the ones in row 5. You can only use the same colours if there are only 2 6s in one of the columns.
HTH
ab

by **re'born** » Sat Jun 16, 2007 2:52 pm

As ab said, coloring just doesn't apply in your case. In fact, different and harder techniques are needed to advance this puzzle. The quickest solution I can find is:

Code: Select all: *--------------------------------------------------------------------* | 3 25 1 | 9 25 6 | 8 4 7 | | 2489 289 7 | 1348 1238 13 | 126 5 1369- | | 2489 6 24589 | 13478 12358 57 | 12 29A 139- | |----------------------+----------------------+----------------------| | 6 127 24 | 5 9 8 | 17 3 14B | | 5 89 489 | 13 7 13 | 46 689- 2 | | 1789 13789 389 | 6 4 2 | 157 89- 159B | |----------------------+----------------------+----------------------| | 178 3578 358 | 1378 13568 9 | 2456 26A 456B | | 278 4 2358 | 378 3568 57 | 9 1 56B | | 19 159 6 | 2 15 4 | 3 7 8 | *--------------------------------------------------------------------*

A={2,6,9} on r37c8, B={1,4,5,6,9} on r4678c9, x = 6, z = 9
The ALS xz-rule implies r23c9, r56c8<>9, solving the puzzle.

Sudoku Players' Forum (clone)

Using Simple Colors Problem

Using Simple Colors Problem

Re: Using Simple Colors Problem

Who is online