| View previous topic :: View next topic |
| Author |
Message |
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
 Posted: Sun Feb 28, 2010 5:26 pm Post subject: Puzzle 10/02/28 (A) |
 |
|
| Code: | +-----------------------+
| 2 . . | . 1 6 | . . . |
| . 8 . | . . . | . . . |
| . . 7 | . . . | . 1 . |
|-------+-------+-------|
| . . . | 3 . . | 1 5 . |
| 1 . . | . 6 . | . . 7 |
| 7 . . | . . . | . 3 6 |
|-------+-------+-------|
| . . . | 8 . . | 5 7 . |
| . . 8 | 4 . 5 | 3 . 1 |
| . . . | . 7 1 | . 8 9 |
+-----------------------+
|
Play this puzzle online at the Daily Sudoku site |
|
| Back to top |
|
 |
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Mon Mar 01, 2010 12:09 am Post subject: |
|
|
Maybe a one-stepper since I used five?
| Quote: | XY (492)
Type 2 UR (39-4)
XYZ (239)
Type 4 UR (29)
DP boxes 147 (34-35-45) |
|
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Mon Mar 01, 2010 3:08 pm Post subject: |
|
|
Three steps, the first two were identical to Martys.
Then I found a skyscraper on 4 that did not directly make any deletions but a simple transport hit the jackpot.
| Code: |
*-----------------------------------------------------------*
| 2 349 349 | 5 1 6 | 7 49 8 |
| 56 8 1 | 7 349 349 | 69 2 35 |
|@456 469 7 | 29 8 239 | 469 1 35 |
|-------------------+-------------------+-------------------|
| 8 2469 2469 | 3 49 7 | 1 5 @24 |
| 1 35 35 | 29 6 2489 | 489 49 7 |
| 7 249 249 | 1 5 489 | 2489 3 6 |
|-------------------+-------------------+-------------------|
|@46 1 246 | 8 39 39 | 5 7 @24 |
| 9 7 8 | 4 2 5 | 3 6 1 |
| 3 245 245 | 6 7 1 | 24 8 9 |
*-----------------------------------------------------------*
|
The skyscraper is in r7c19 marked @ with pincers in r3c1 and r4c9; no deletions are possible since the pincers are not in the same levels.
However a simple transport does the deed. If r3c1=4, then r3c7<>4, then r1c8=4; therefore r5c8<>4.
In Eureka notation the transport is: (4)r3c1 - (4)r3c7 = (4)r1c8; r5c8<>4.
Ted |
|
| Back to top |
|
|
Luke451
Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California
|
| Posted: Mon Mar 01, 2010 11:06 pm Post subject: |
|
|
Thanks to help from folks like storm_norm I've been trying to take Bug-Lite out of my end-game arsenal and more into the mainstream.
Here's the SSTS position with Marty's “Deadly Pattern boxes 147” marked.
| Code: | *-----------------------------------------------------------*
| 2 *349 *349 | 5 1 6 | 7 49 8 |
| 456 8 1 | 7 349 349 | 469 2 35 |
| 456 469 7 | 29 8 2349 | 46 1 35 |
|-------------------+-------------------+-------------------|
| 8 2469 2469 | 3 49 7 | 1 5 24 |
| 1 *35 *35 | 29 6 2489 | 489 49 7 |
| 7 249 49 | 1 5 489 | 2489 3 6 |
|-------------------+-------------------+-------------------|
| 46 1 246 | 8 39 39 | 5 7 24 |
| 9 7 8 | 4 2 5 | 3 6 1 |
| 3 *245 *245 | 6 7 1 | 24 8 9 |
*-----------------------------------------------------------* |
There are "external outs" which prove useful. They are the values outside the pattern that could possibly prevent it.
| Code: | *-----------------------------------------------------------*
| 2 349 349 | 5 1 6 | 7 *49 8 |
| 456 8 1 | 7 349 2349 |-4269 249 35 |
| 456 469 7 | 29 8 2349 |-4269 1 35 |
|-------------------+-------------------+-------------------|
| 8 2469 2469 | 3 49 7 | 1 5 24 |
| 1 35 35 | 29 6 2489 | 2489 249 7 |
| 7 249 249 | 1 5 2489 | 2489 3 6 |
|-------------------+-------------------+-------------------|
| 46 1 246 | 8 39 39 | 5 7 24 |
| 9 7 8 | 4 2 5 | 3 6 1 |
| 3 245 245 | 6 7 1 |*42 8 9 |
*-----------------------------------------------------------* |
Both (4)r1c8 and (4)r9c7 can’t be false, or the (345) DP would exist. At least one of them must be true. Since (4)r23c7 can see both of those 4’s, they both can be zapped, solving the puzzle.
There is also a strong link between the group 9s in r1c23 and the group 2s in r9c23 that can be exploited in the same way.
We do this all the time for URs, so maybe it's time Bugs and Mugs and other DPs got into the act a little more  . |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Fri Mar 05, 2010 6:42 pm Post subject: |
|
|
| Code: | c48r5 Skyscraper <> 2 r2c6,r3c7
c48\r35 Sashimi X-Wing <> 9 r3c7
r27c56 <39> UR Type 2 <> 4 r2c178,r3c6
r9c1 2-String Kite <> 4 r3c7
|
|
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
