I knew when constructing puzzles for this past week that it would end up pretty tough across the board. I had certain themes in mind and when constructing for a particular goal you cannot always tailor the timing precisely. I believe — except for Monday’s puzzle — everything was rated for at least 5 minutes. It is probably asking too much to expect a full week to “feel perfectly balanced” when there are six different styles being presented.

So, while it may be impossible to avoid “hard” weeks in the future, this did seem an apt time to return to discussing some of these puzzles. I got a specific request to describe Saturday’s Battleships in logical terms, so that is what I’ll cover today.

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PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: X Marks the Spot

Rules: Standard Battleships rules. Notice the larger than usual fleet beneath the puzzle.

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 = 5:45, Master = 8:30, Expert = 17:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

This is a “Franken-Friday” puzzle variation.

Theme: Corrupted Regions

Rules: Variation of standard Star Battle rules. Two stars per row and column, but no region has exactly two stars. Each region must contain some number of stars other than 2, including possibly no stars at all.

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

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:30, Expert = 9:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: Today’s date, which is featured twice in the clues

Rules: Standard Battleships 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 = 2:00, Master = 3:00, Expert = 6:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Broken Window

Rules: Standard Star Battle rules. Two stars per row, column, and region.

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

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:00, Expert = 10:00

Solution: PDF

Note: Follow this link for other classic Star Battles and this link for Star Battle variations. If you are new to this puzzle type, here are our easiest Star Battles to get started on. More Star Battle puzzles can be found in The Art of Puzzles, in the book Star Battle by JinHoo Ahn, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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)

Theme: Author’s monogram

Rules: Standard Star Battle rules. Two stars per row, column, and region.

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

Time Standards (highlight to view): Grandmaster = 2:45, Master = 4:30, Expert = 9:00

Solution: PDF

Note: Follow this link for other classic Star Battles and this link for Star Battle variations. If you are new to this puzzle type, here are our easiest Star Battles to get started on. More Star Battle puzzles can be found in The Art of Puzzles, in the book Star Battle by JinHoo Ahn, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Eighth in a series with puzzle solving tips. This time with advice on battleships puzzles, particularly missing clues and subs.

Solving Battleships is an odd experience for me. I think I want to enjoy them, but I’m not sure I ever really do very much. See, they were the first logic puzzle type I ever grew to love. But that means they also became the first logic puzzle type to bore me, and I’ve now been in the “bore me” stage for over half my life. And there is so much sameness in the Battleships you can find in the world right now. ~99% are randomly generated, ~99% give all of the outside clues which limits the challenge, ~99% solve by placing the largest ship(s) in the only possible spots and being good at bookkeeping of seas afterwards. As a member of the puzzling 1%, I am looking for something more. This week I tried to vary the formula a bit to make some more interesting — or at least different — puzzles.

(more…)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: The Bermuda Quadrangle? The missing radar clues will complicate the solve.

Rules: Standard Battleships 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 Standard: Battleships Grandmaster = 3:45, Master = 7:00, Expert = 14:00

Solution: PDF

Note: Advice on solving this puzzle has now been posted in “Ask Dr. Sudoku #8“

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: Just Try Two Find Us

Rules: Standard Battleships 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 Standard: Battleships Grandmaster = 1:45, Master = 2:45, Expert = 5:30

Solution: PDF