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2x Puzzles dedicated to Keith, but for everyone

dailysudoku.com Forum Index -> Puzzles by daj

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daj95376

Joined: 23 Aug 2008
Posts: 3854

Posted: Tue Apr 06, 2010 4:52 pm Post subject: 2x Puzzles dedicated to Keith, but for everyone

Keith: check out URs after basics

Code:

+-----------------------+
| 7 8 . | 2 . . | . . 6 |
| 2 9 3 | . 1 8 | . . . |
| . 4 . | . . 7 | . 8 . |
|-------+-------+-------|
| 6 . . | . . . | . . . |
| . 2 . | . 8 5 | . . . |
| . 5 8 | . 6 4 | 3 . 2 |
|-------+-------+-------|
| . . . | . . 2 | 7 . . |
| . . 2 | . . . | . 6 . |
| 8 . . | . . 6 | . . 9 |
+-----------------------+

Play this puzzle online at the Daily Sudoku site

Keith: check out URs after basics and X-Wing

Code:

+-----------------------+
| . 4 . | . . . | . 3 8 |
| 2 5 6 | 8 3 . | 1 9 . |
| . 8 3 | . . . | . . 2 |
|-------+-------+-------|
| . 1 . | 9 . . | . 6 . |
| . 9 . | . 4 . | . . . |
| . . . | . . 7 | 3 . 9 |
|-------+-------+-------|
| . 7 . | . . 1 | 9 . 3 |
| 5 3 . | 7 . . | . . . |
| 9 . 1 | . . 5 | 7 . 4 |
+-----------------------+

Play this puzzle online at the Daily Sudoku site

keith

Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

Posted: Wed Apr 07, 2010 1:28 am Post subject:

After basics:

Code:

+-------------+-------------+-------------+
| 7 8 5 | 2 4 3 | 19 19 6 |
| 2 9 3 | 6 1 8 | 4 57 57 |
| 1 4 6 | 5 9 7 | 2 8 3 |
+-------------+-------------+-------------+
| 6 17 147 | 3 2 19 | 89 459 58 |
| 3 2 14 | 179 8 5 | 6 49 17 |
| 9 5 8 | 17 6 4 | 3 17 2 |
+-------------+-------------+-------------+
| 4 6 9 | 18 5 2 | 7 3 18 |
| 5 37 2 | 189 37 19 | 18 6 4 |
| 8 137 17 | 4 37 6 | 5 2 9 |
+-------------+-------------+-------------+

Quote:

For the first one, a UR1 and an XY-wing.

I'm probably missing something.

Quote:

(Surely I am, for I actually used the SS 1 in R67, which is a one-stepper.)

Keith

keith

Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

Posted: Wed Apr 07, 2010 3:30 am Post subject:

No. 2, after basics:

Code:

+-------------+-------------+-------------+
| 17 4 9 | 2 17 6 | 5 3 8 |
| 2 5 6 | 8 3 4 | 1 9 7 |
| 17 8 3 | 15 157 9 | 6 4 2 |
+-------------+-------------+-------------+
| 38 1 7 | 9 28 238 | 4 6 5 |
| 368 9 258 | 56 4 38 | 28 7 1 |
| 4 26 258 | 156 15 7 | 3 28 9 |
+-------------+-------------+-------------+
| 68 7 28 | 4 26 1 | 9 5 3 |
| 5 3 4 | 7 9 28 | 28 1 6 |
| 9 26 1 | 3 268 5 | 7 28 4 |
+-------------+-------------+-------------+

Quote:

I used a UR1 17, X 2, UR6 38, Bug +8

Keith

Marty R.

Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

Posted: Wed Apr 07, 2010 5:06 am Post subject:

For #1, I used the Type 1 on 37 and finished with the W-Wing on 19. There was the almost Type 6 on 17 which made two eliminations, but it didn't take me very far so I didn't use it.

daj95376

Joined: 23 Aug 2008
Posts: 3854

Posted: Wed Apr 07, 2010 5:07 am Post subject:

First puzzle: Two URs with a cell, r9c2, in common.

Code:

<17> UR [ (4)r4c3 = (3)r9c2 ] => 3-7-3-7 DP in r89c25 ==>> r4c3=4

r89c25 <37> UR Type 1
r49c23 <17> UR Type ?
+-------------+-------------+-------------+
| 7 8 5 | 2 4 3 | 19 19 6 |
| 2 9 3 | 6 1 8 | 4 57 57 |
| 1 4 6 | 5 9 7 | 2 8 3 |
+-------------+-------------+-------------+
| 6 17 147 | 3 2 19 | 89 459 58 |
| 3 2 14 | 179 8 5 | 6 49 17 |
| 9 5 8 | 17 6 4 | 3 17 2 |
+-------------+-------------+-------------+
| 4 6 9 | 18 5 2 | 7 3 18 |
| 5 37 2 | 189 37 19 | 18 6 4 |
| 8 137 17 | 4 37 6 | 5 2 9 |
+-------------+-------------+-------------+

Alternate perspective: Perform UR Type 1 and notice remaining cells in second UR.

Code:

r89c25 <37> UR Type 1 => r9c2<>37
r49c23 <17> UR Type ? => r4c3<>1
+-------------+-------------+-------------+
| 7 8 5 | 2 4 3 | 19 19 6 |
| 2 9 3 | 6 1 8 | 4 57 57 |
| 1 4 6 | 5 9 7 | 2 8 3 |
+-------------+-------------+-------------+
| 6 *7 @4-1 | 3 2 19 | 89 459 58 |
| 3 2 14 | 179 8 5 | 6 49 17 |
| 9 5 8 | 17 6 4 | 3 17 2 |
+-------------+-------------+-------------+
| 4 6 9 | 18 5 2 | 7 3 18 |
| 5 3 2 | 189 7 19 | 18 6 4 |
| 8 *1 *7 | 4 3 6 | 5 2 9 |
+-------------+-------------+-------------+

daj95376

Joined: 23 Aug 2008
Posts: 3854

Posted: Wed Apr 07, 2010 5:14 am Post subject:

Second puzzle: Two URs with a cell, r3c5, in common.

Code:

<15> UR [ (6)r6c4 = (7)r3c5 ] => 7-1-7-1 DP in r13c15 ==>> r6c4=6

r13c15 <17> UR Type 1
r36c45 <15> UR Type ?
+-------------+-------------+-------------+
| 17 4 9 | 2 17 6 | 5 3 8 |
| 2 5 6 | 8 3 4 | 1 9 7 |
| 17 8 3 | 15 157 9 | 6 4 2 |
+-------------+-------------+-------------+
| 38 1 7 | 9 28 238 | 4 6 5 |
| 368 9 258 | 56 4 38 | 28 7 1 |
| 4 26 258 | 156 15 7 | 3 28 9 |
+-------------+-------------+-------------+
| 68 7 28 | 4 26 1 | 9 5 3 |
| 5 3 4 | 7 9 28 | 28 1 6 |
| 9 26 1 | 3 268 5 | 7 28 4 |
+-------------+-------------+-------------+

Alternate perspective: Perform UR Type 1 and notice remaining cells in second UR.

Code:

r13c15 <17> UR Type 1 => r3c5<>17
r36c45 <15> UR Type ? => r6c4<>5
+-------------+---------------+-------------+
| 1 4 9 | 2 7 6 | 5 3 8 |
| 2 5 6 | 8 3 4 | 1 9 7 |
| 7 8 3 | *1 *5 9 | 6 4 2 |
+-------------+---------------+-------------+
| 38 1 7 | 9 28 238 | 4 6 5 |
| 368 9 258 | 56 4 38 | 28 7 1 |
| 4 26 258 | @6-5 *1 7 | 3 28 9 |
+-------------+---------------+-------------+
| 68 7 28 | 4 26 1 | 9 5 3 |
| 5 3 4 | 7 9 28 | 28 1 6 |
| 9 26 1 | 3 268 5 | 7 28 4 |
+-------------+---------------+-------------+

This type of overlapping URs occurred three times in a group of 99 puzzles from my puzzle generator.

I seem to recall Norm providing a similar operation but under a different technique name. Maybe he'll return and enlighten us/me.

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