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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Thu Mar 24, 2011 8:03 pm Post subject: Puzzle 11/03/24: ~ Difficult++ |
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Code: | +-----------------------+
| 5 7 . | . 2 . | . 1 9 |
| 4 1 . | . . 8 | . . 5 |
| . . 2 | . . 1 | . . . |
|-------+-------+-------|
| . . . | . 9 6 | . . . |
| 1 . . | 2 7 . | . . . |
| . 6 9 | 8 . 3 | . 2 . |
|-------+-------+-------|
| . . . | . . . | 9 . . |
| 3 . . | . . 9 | . . 1 |
| 8 9 . | . . . | . 4 . |
+-----------------------+
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peterj
Joined: 26 Mar 2010 Posts: 974 Location: London, UK
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Posted: Thu Mar 24, 2011 10:51 pm Post subject: |
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Ouch! 3s seems to be the key...
Quote: | als(3458=2)r7c2589 - als(2=36)r9c59 ; r9c7<>3
grouped-kite(3) r3, c7 ; r5c2<>3
xy-chain ; (3=8)r3c2 - (8=4)r5c2 - (4=5)r7c2 - (5=1)r9c3 - (1=5)r9c4 - (5=6)r8c4 - (6=3)r1c4 ; r1c3<>3
colouring(3) ... ; r5c9<>3, r4c3<>3
xy-wing(48-5)r5c2 ; r4c2<>5, r89c3<>5 |
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JC Van Hay
Joined: 13 Jun 2010 Posts: 494 Location: Charleroi, Belgium
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Posted: Fri Mar 25, 2011 9:51 pm Post subject: |
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A possible shortest path on the 3s :
Quote: | 4 SIS X Chain on 3 : B1 B3 C4 C8 : 3r12c3=3r4c8 => r4c3<>3
6 "native" SIS AIC : 4R5 (45)R7C2 5R9 (56)R8C4 6C5 3R2 : 4r5c3=3r2c3 => r5c3<>3; LC(3)C2; 2 singles
5 "native" SIS AIC : 7R8 4R8 8C5 8C9 6R5 : 7r8c7=6r5c7 => r8c7<>6
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Sat Mar 26, 2011 12:07 am Post subject: |
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I generated a new batch of puzzles where many turned out to be more difficult than posted in awhile. This was the first.
Code: | r79c34 <15> UR Type 4.2243 <> 5 r7c34
+-----------------------------------------------------+
| 5 7 368 | 36 2 4 | 38 1 9 |
| 4 1 36 | 9 36 8 | 2 7 5 |
| 9 38 2 | 7 5 1 | 4 368 368 |
|-----------------+-----------------+-----------------|
| 2 358 358 | 4 9 6 | 1 38 7 |
| 1 348 348 | 2 7 5 | 368 9 368 |
| 7 6 9 | 8 1 3 | 5 2 4 |
|-----------------+-----------------+-----------------|
| 6 45 147 | 13 48 27 | 9 358 238 |
| 3 2 457 | 56 48 9 | 678 568 1 |
| 8 9 15 | 15 36 27 | 367 4 236 |
+-----------------------------------------------------+
# 50 eliminations remain
AIC: (3)r9c5 = (3-1)r7c4 = (1-7)r7c3 = r8c3 - r8c7 = (7)r9c7 => r9c7<>3
r3c7 2-String Kite (grouped) <> 3 r5c2
XY-Loop: (3=6)r1c4 =5r8c4 =1r9c4 =5r9c3 =4r7c2 =8r5c2 =3r3c2 =6r2c3 =3r2c5 - loop
=> r1c3<>3; r8c3<>5; r4c2<>8
r14c3 Skyscraper <> 8 r3c8,r5c7
XY-Chain: (8=3)r4c8 =5r4c2 =4r7c2 =8r5c2 => r4c3,r5c9<>8
r1c8 2-String Kite <> 3 r7c4
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JC Van Hay
Joined: 13 Jun 2010 Posts: 494 Location: Charleroi, Belgium
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Posted: Sat Mar 26, 2011 7:53 am Post subject: |
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Reviewing previous path, the following is even shorter, with the same eliminations ... Code: | 4 SIS t-Chain on 3 : r12c3=r3c2-r3c8*9=r1c7-r1c4=r7c4-[r7c8 AND r3c8*]=r4c8 => r4c3<>3
5 "native" SIS AIC with AHS : 4r5c3=47r78c3-1r7c3=(1-3)r7c4=3r9c5-3r2c5=3r2c3 => r5c3<>3; LC(3)C2; 2 singles
4 "native" SIS ALS XZ-Rule : (65=8)r8c48-(8=36)r4c8,r5c7 => r8c7<>6 |
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