| Thurs 28 Dec (Thursday, 28th December 2006) | 
| PuzzleLover Kwon-Tom Obsessive
 Puzzles: 1033
 Best Total: 38m 17s
 | Posted - 2006.12.28 05:14:31 I got this far with patterns.  Finishing from here was basically trial and error.  Am I missing some patterns or easy lookaheads?  Thanks.
 
 
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| Gadget1903 Kwon-Tom Addict
 Puzzles: 325
 Best Total: 23m 39s
 | Posted - 2006.12.28 05:40:31 You can get a little further realizing that a line above the 1 at r2c9 creates a quick inner loop.
 
 After that I guessed the rest.
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| m2e Kwon-Tom Obsessive
 Puzzles: 607
 Best Total: 16m 43s
 | Posted - 2006.12.28 06:55:00 Muck around with the 1 @ r4c6. That one should carry you to the end of the puzzle i think.
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| Filthy Kwon-Tom Obsessive
 Puzzles: 1376
 Best Total: 17m 21s
 | Posted - 2006.12.28 07:37:53 You're missing this common pattern:
 
 becomes
 
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| m2e Kwon-Tom Obsessive
 Puzzles: 607
 Best Total: 16m 43s
 | Posted - 2006.12.28 07:52:20 I always forget that one
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| procrastinator Kwon-Tom Obsessive
 Puzzles: 1083
 Best Total: 12m 56s
 | Posted - 2006.12.28 09:26:09 There's simple counting to be done down the bottom, which also gives you another line on the 2 just above.
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| foilman Kwon-Tom Admin
 Puzzles: 3939
 Best Total: 24m 6s
 | Posted - 2006.12.28 10:22:08 
 Yes, I saw that too - the 4th row from the bottom has just one unknown, and 3 lines, so you know the remaining one must be a line too (to keep the number of lines even).Quote: | Originally Posted by procrastinator There's simple counting to be done down the bottom, which also gives you another line on the 2 just above. | 
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| PuzzleLover Kwon-Tom Obsessive
 Puzzles: 1033
 Best Total: 38m 17s
 | Posted - 2006.12.29 04:06:30 I forgot that upper right pattern, thanks.
 
 
 I'm not sure which 2 procrastinator is referring to, but I like that row 7 observation!  When you're counting, do you tend to look for regions, cut sets, or both?  A cut set across row 7 makes the line at r7c6.5 clear (once you look at row 7).  I find it harder to count the lines entering the bottom region on this one.Quote: | Originally Posted by foilman Quote: | Originally Posted by procrastinator There's simple counting to be done down the bottom, which also gives you another line on the 2 just above. | 
Yes, I saw that too - the 4th row from the bottom has just one unknown, and 3 lines, so you know the remaining one must be a line too (to keep the number of lines even). | 
 I'm not finding any cut sets or region entries/exits where I can visualize a count on the top.
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| procrastinator Kwon-Tom Obsessive
 Puzzles: 1083
 Best Total: 12m 56s
 | Posted - 2006.12.29 04:50:42 
 Quote: | Originally Posted by puzzlelover I'm not sure which 2 procrastinator is referring to,
 
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The counting argument gives you a line on a 1, there's a 2-with-an-x just above it, and now one of the three possible pairs of lines doesn't work.
 
 
 Quote: | Originally Posted by puzzlelover When you're counting, do you tend to look for regions, cut sets, or both?
 
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If I'm understanding you correctly, then any region has a cutset isolating it from the rest of the graph (The set of (potential) edges which join a point in the region to a point outside). If the region you choose is something like "the bottom four rows", then your cutset will be a single row of vertical edges. Those are the easiest cutsets to count, but some regions don't have a neat cutset like that. So I first detect the (near)-isolated region, then look for the easiest cutset to count. If there is a single row of edges then that will be easiest so I look for a cutset of that ilk first.
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| PuzzleLover Kwon-Tom Obsessive
 Puzzles: 1033
 Best Total: 38m 17s
 | Posted - 2006.12.29 05:06:47 
 Now I see it, but only after placing a few moves.  You're a better reader than I am!  Thanks.Quote: | Originally Posted by procrastinator Quote: | Originally Posted by puzzlelover I'm not sure which 2 procrastinator is referring to,
 
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The counting argument gives you a line on a 1, there's a 2-with-an-x just above it, and now one of the three possible pairs of lines doesn't work. | 
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| Jankonyex Kwon-Tom Obsessive
 Puzzles: 5687
 Best Total: 9m 35s
 | Posted - 2006.12.29 08:18:17 I remember... I made this then finished the puzzle.
 
 
 Last edited by Jankonyex - 2006.12.29 08:20:11 | 
| PuzzleLover Kwon-Tom Obsessive
 Puzzles: 1033
 Best Total: 38m 17s
 | Posted - 2006.12.30 06:15:27 
 Very nice pattern, noting 4 lines must leave the empty square down/left from 2!  I'm impressed by your ability to quickly see patterns like this in real time.  No wonder you're consistently high in the leaders list!Quote: | Originally Posted by jankonyex I remember... I made this then finished the puzzle. | 
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