PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between edgex mode where left click+drag draws lines and right click marks X’s and a line drawing mode to mark the dominoes.)

This is a “Twisted Tuesday” puzzle variation.

Theme: Double Domino – both domino-based clue groupings, and a domino-based loop.

Rules: Standard Slitherlink rules; also, the interior of the loop must be divisible into dominoes (1×2 rectangles) in at least one way without any overlaps.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 4:30, Master = 7:00, Expert = 14:00

Editorial Note: This puzzle is a fair bit more difficult than our usual Tuesday puzzles, but this may be a side effect of the new Twisted Tuesday format.

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between Battleships placement and line drawing modes.)

This is a “Twisted Tuesday” puzzle variation.

Theme: A Fleet of Clues

Rules: Variation of Battleships rules. Place the fleet of ships in the grid so that no ships touch each other, even diagonally. The grid contains internal clues (a number and an arrow) that show how many ship segments are in the indicated direction. All remaining cells containing neither a ship nor a clue must be able to form a single loop, as in a Yajilin puzzle (see for example here but note the “black square rules” are replaced with battleships placement rules).

Answer String: For each row from top to bottom, enter the number of the first column from the left where a ship segment appears. If the row is empty, enter 0. Enter these numbers as a single string with no separators.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:00, Expert = 8:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Mostly themeless? A mostly straight-forward puzzle to start the week.

Rules: Standard Masyu rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:15, Expert = 2:30

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools in edgex mode where left click+drag draws lines and right click marks X’s)

Theme: Triples

Rules: Standard Slitherlink rules.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:30, Expert = 3:00

Solution: PDF

Ninth in a series with puzzle solving tips. This time with advice on Slitherlink and loop puzzles in general.

Even if you had a good time on the TIME Slitherlink, the following walk-through might offer you some new tips — besides just memorizing Slitherlink patterns — to get better at loop puzzles.

(more…)

PDF

or solve online (using our beta test of Penpa-Edit tools in edgex mode where left click+drag draws lines and right click marks X’s)

Theme: Just in TIME? A hard Slitherlink puzzle from US Puzzle Team member Thomas Snyder, one of the “Answer Men” profiled in this week’s issue (subscription required).

Rules: Standard Slitherlink rules.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 4:30, Expert = 9:00

Note: Advice on solving this puzzle has now been posted in “Ask Dr. Sudoku #9”

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools in edgex mode where left click+drag draws lines and right click marks X’s)

Theme: All for One and One for All

Rules: Standard Slitherlink rules.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 5:00, Expert = 10:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools in edgex mode where left click+drag draws lines and right click marks X’s)

Theme: Parquet

Rules: Standard Slitherlink rules.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:15, Expert = 2:30

Solution: PDF

Fifth in a series with puzzle solving tips. This time, with some advice on global constraints that arise in loop puzzles.

Some of you have asked why I don’t put “general tips” up before I post any puzzles. I find that learning how to solve puzzles is more interesting than reading how to do every single step. I won’t post a list of the top 20 Slitherlink patterns you should memorize, for example, on the rules and info page. Most of you would probably get more enjoyment figuring those out for yourself. But, after you’ve solved a challenge, I do like highlighting some of the things as constructor I tried to include, perhaps as a lesson for the future. This is what I will do this week with parity constraints for the Friday Masyu.

(more…)

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Almost Twisted! – Slightly imperfect, but more difficult as a result.

Rules: Standard Masyu rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standard: Masyu Master = 2:00, Expert = 6:00, Novice = 20:00

Note: Advice on solving this puzzle has now been posted in “Ask Dr. Sudoku #5”

Solution: PDF and solving video.