JCO Website (Puzzles for the manual solver)

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Recent Puzzles (*1*)

Puzzle SL#33 (overall #144) (9x9 Slitherlink; proposed November 10, 2026)

I propose the following (not so tough) Slitherlink puzzle (nice patterns!).

(Source: Simon Tatham's Collection)

Slitherlink 9x9

Hint (Update 1: Basic moves)
  .---------------------------------------.
  | .   .   .   .   .   .   .   .   .   . |
9 |           2   2       2       3       |
  | .   .   .   .   .   .   .   .   .   . |
8 |           2   1   3           2       |
  | .   .   .   .   .   .   .   .   .   . |
7 |   3   1       2       2       2   3   |
  | .   .   .   .   .   .   .   .   .   . |
6 |   3               3       2   2       |
  | .   .   .   .   .   .   .   .   .   . |
5 |               2               3   1   |
  | .   .   .   .   .   .   .   .   .   . |
4 |   1   1   1                       1   |
  | .   .   .   .   .   .   .   .   .   . |
3 |           2               1           |
  | .   .   .   .   .   .   .   .   .   . |
2 |   2   1   1   3   2                   |
  | .   .   .   .   .   .   .   .   .   . |
1 |   3       2       2   2   2   2   3   |
  | .   .   .   .   .   .   .   .   .   . |
  '---------------------------------------'
      a   b   c   d   e   f   g   h   i    SL
    
Update 1 (Nov 13, 2026)
    
After 19 basic moves, including the pattern
._
|3
  2
    2
      3|
     --'

we reach the following configuration

  .---------------------------------------.
  | .   .   .   .___.___.   .   .   .   . |
9 |           2 | 2       2       3       |
  | .   .   .___.   .___.   .   .   .   . |
8 |           2   1 | 3           2       |
  | .___.   .   .   .   .   .   .   .   . |
7 |   3   1       2       2       2   3 | |
  | .___. x .   .   .   .   .   .   .___. |
6 |   3               3       2   2       |
  | .___.   .   .   .   .   .   .   .   . |
5 |               2               3 | 1   |
  | .   .   .   .   .   .   .   .___.   . |
4 |   1   1   1                       1   |
  | .   .   .   .   .   .   .   .   .___. |
3 |           2               1         | |
  | .   .   .   .   .   .   .   .   .   . |
2 |   2   1   1   3   2                   |
  | .   .   .   .   .   .   .   .   .   . |
1 | | 3       2       2   2   2   2   3 | |
  | .___.   .   .   .   .   .   .   .___. |
  '---------------------------------------'
      a   b   c   d   e   f   g   h   i    SL

How to make progress from here ?
    

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Past Puzzles (*143*)

Past Problems (*8*)

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Created: February 12, 2024

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