Archive for the ‘Other Puzzles’ Category:

Sunday Surprise #9 – Matryoshka Fillomino

Today’s surprise comes from Nikolai Beluhov, a graduate student of mathematical logic who has been sharing some creative puzzle ideas with me recently. Some of them have ended up on his new puzzle blog Puzzled By Titles. This puzzle has become a Sunday Surprise.

Much like a set of Matryoshka dolls, this Fillomino is a puzzle with many layers. Remove the outer border and a new valid Fillomino arises. Keep doing this all the way down to the very center where a 2×2 puzzle awaits. The layers have a wide variety of difficulty and required logical strategies. Can you solve them all?

Fillomino by Nikolai Beluhov

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Matryoshka (nesting property) across 5 puzzles

Rules: Standard Fillomino rules.

Answer String: For each puzzle from largest (10×10) to smallest (2×2), enter the numbers placed in each cell along the upper-left to lower-right diagonal in order. Separate each puzzle’s entry by a comma (Your answer will be of the form AAAAAAAAAA,BBBBBBBB,CCCCCC,DDDD,EE).

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Sunday Surprise #8 – Mystery Tapa

Today’s surprise originally comes from Hans van Stippent, with some edits by me (Thomas Snyder) to increase the challenge and rewards of the solve. Together, we present this creative “Mystery Tapa” where all the clues (any value from 1-8) have been replaced with ?’s.

Tapa by Hans van Stippent and Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Clueless?

Rules: Variation of Tapa rules. All clue numbers (1 and above) have been replaced with question marks.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row entry from the next with a comma. A double-digit number should have both digits entered.

Solution: PDF

Sunday Surprise #7 – Welcome to Serkan Yürekli

Editor’s Note: While our Sunday Surprises are meant to be unexpected, today’s surprise should be a double surprise for you. Besides the bonus puzzle, it is my great pleasure to announce that one of the world’s best puzzlemakers and the inventor of Tapa, Serkan Yürekli, is joining us as a regular contributor. (If you haven’t yet, you should check out his Tapa Variation Contests that are starting again this weekend and his Classic Tapa Contest that starts next week.)

I asked Serkan, for his debut week, to provide some of the puzzle styles I know him best for and I hope you will enjoy what is in store. Today brings a “The Persistence of Memory” puzzle that Serkan wrote with GMPuzzles in mind.

The Persistence of Memory by Serkan Yürekli

(View image directly for larger form.)

(PNG with extra lines for solvers who want to flood-fill the path)

or solve online (using our beta test of Penpa-Edit tools using a composite mode where left click inside cell shades square, left click + drag draws line segment, right click inside cell adds dot, and right click on cell edge adds an x.)

PDF

Theme: GMPuzzles

Rules: Find a path from one dot to the other by moving horizontally or vertically between adjacent squares. The path cannot touch itself, even diagonally. All highlighted regions must be used, and may be re-entered. If two or more highlighted regions have the same shape and orientation, then how the path passes through those shapes must be identical. Or see here.

Answer String: For each marked row, enter the size of each group of cells used by the path from left to right. Separate each row with a comma.

Time Standards (highlight to view): Grandmaster = 7:30, Master = 10:30, Expert = 21:00

Solution: PDF

Championship Chatter – How Many Roads …?

I received a lot of “pre-criticism” about having made a Counting Puzzle for the USPC. I have been rather outstated as a solver in not liking these puzzles because of the difficulty of confirming one’s answer — particularly in the old -5 point days for a mistake that would frequently cost me for even attempting and getting close to the right answer. And I often don’t get the choice to skip it when I’m close to finishing the test.

But that doesn’t mean I’ve never been called on to write Counting Puzzles. I wrote a GAMES article/Puzzlecraft chapter on the topic. And I gave it another attempt on this USPC. Call it an experiment to see if I could make anything my audience would accept as a good puzzle.

My first concept was to make a heavy path puzzle with lots of forced segments due to arrows, but not a single solution to give it a “counting” aspect. While I figured good solvers would be able to get to a “trivial” state to count a handful of total paths, all of my initial designs ended up feeling more like a broken path puzzle than a good counting puzzle so a changed goals slightly. I wondered: can I make a few very simple counting challenges work together with some simple math to be a fair challenge. Basically, something where good observation could reduce the problem into something much more tractable. And if this is testing both observation and problem solving skills in an unfamiliar setting, all the better.

Even with the “simple” format below that even had the surprise of very basic multiplication built in, the successful answer rate was quite low compared to my own expectations. And at least one solver has complained about getting 99.991% of the correct answer and getting zero credit. In my evaluation, with three small counting puzzles and a meta puzzle of building the math equation, that answer is 75% correct in the same way some of the answers in the 52k range were. All from counting one of the component puzzles one lower than expected.

So, did you think this was an appropriate USPC challenge? Did this soften or strengthen opinions against counting puzzles? Are counting puzzles still the brussel sprouts of the USPC buffet? I’ve only heard positives from people that actually got the puzzle correct so I do have to think score results often bias counting puzzle reviews (my strongly negative reviews have certainly followed my average score of -5 on these puzzles over the years).

Pathfinder by Thomas Snyder

PDF

Theme: Symmetry, mainly

Rules: Count the number of different paths from Start (S) to Finish (F). You cannot use an intersection or a path segment more than once. Path segments with arrows can only be used in the indicated direction.

Answer String: For the USPC, the answer string was the number of paths. For this week, you can just hit the solved button on an honor system if you think you’ve solved it.

Solution: PDF

And if you want an extra challenge, solve this bonus puzzle where an arrow has been removed. It’s one step up from the original puzzle but should be just as simple to break into constituent parts if you’ve mastered the first.

Ask Dr. Sudoku – Championship Chatter

Last Saturday finished another 6 week cycle of offerings from Grandmaster Puzzles. It also finished a rather busy 6 weeks of puzzle construction and testing, including three different puzzle championship rounds. Two of these have now been hosted (the US Sudoku Qualifying Test/Grand Prix Contest, and the US Puzzle Championship) and one will be a future surprise. This gives me reason to think a pause for some reflection and discussion about some of these puzzles would be a valuable use of the “gap” time before our next spurt of new puzzles and possibly new genres begins. [It also gives me a chance to hopefully address some server issues.]

The USPC is one of the few championships that follows the World Puzzle Federation’s model of puzzle balance including observational puzzles, word manipulation puzzles, and often some “trick” puzzles alongside a mix of classic constraint satisfaction types and variants. I figured — given existing contributors — that I would be most called upon to make some innovative word and observational puzzles alongside some original (read: previously unseen) variants that would hold new surprises for all solvers. The first puzzle I wanted to highlight is one that is meant to be recognizable and friendly to even the casual solver: the USPC Word Search.

I had a few ideas in mind this year for creating an interesting word search, and settled on a variety rebus gimmick where entries may or may not contain a shortened set of characters in a single square. Having previously used digit word phrases for a Sudoku Masterpieces puzzle (Some Err1ous Spelling!) and having much of that research on hand, I took my time getting a good interlinked set of “Digi2rds” together for the USPC puzzle. The missing middle shaped like an octothorpe was another goal I had in mind to give the puzzle some character. I also laid some traps around the middle for solvers trying to intuit words too soon. While many solvers will turn their noses up at a word search, I still see great value in having such puzzle styles represented on a puzzle championship. I hope I managed to give an intriguing challenge with the puzzle below.

Word Search by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab mode to shift between line drawing, letter/number entry, and shading modes)

Theme: Hidden Numbers

Rules: Standard Word Search rules. Also, a digit may be used in place of its letters when spelled out. For example, “DIGIT WORD SEARCH” might appear in the grid as “DIGI2RDSEARCH”. 25 characters are missing from the grid and must be identified to complete the puzzle.

Answer String: For the USPC, the answer string was the 25 missing characters in order. For this week, you can just hit the solved button on an honor system if you think you’ve solved it.

Solution: PDF

Sunday Surprise #6 – US Championship

I had not intended to have a repeat author for a Sunday Surprise so soon, but Craig Kasper sent along a really nice surprise sudoku to mark the US National Championship we’ve been focusing our attention on all weekend. See if you can find your way through to the very end.

Surprise Puzzle by Craig Kasper

PDF

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

Theme: That US national championship happening this weekend; speaking of which, congratulations to the top finishers at the US Puzzle Championship, whomever you turn out to be.

Rules: Standard Sudoku rules. Also, the regions are irregularly shaped; instead of numbers, use the letters in “I’D GOLF, MAN” once in each row, column, and region.

Answer String: Enter the letters in the third column, from top to bottom, followed by the letters in the seventh column, from top to bottom. USE CAPITAL LETTERS.

Solution: PDF

Sunday Surprise #5 – Seeing Stars (and a contest)

Today’s surprise marks the occasion of Grant Fikes’ 26th birthday. Grant has written a surprise puzzle hunt-style puzzle that will solve to a two word answer. This is likely more challenging than our earlier “Word Search” surprise on April 1st, but we hope it is enjoyable to those who give it a shot while celebrating Grant’s birthday.

Note: the first 26 solvers (or all those who solve it within a week if fewer than 26 solve it by then) will be entered into a random drawing for a copy of Grant’s “Battle of LITS” board game.

Surprise Puzzle by Grant Fikes

PDF

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

Answer String: Enter the two word answer in all capital letters, with a single space between words.

Solution: PDF

Update (6/2/13): There have been 27 solvers in the week since this puzzle posted and all of those names will be placed into a drawing sometime shortly. Watch here for further updates.

**While this was initially not a numbered Grant opus, we are calling it #48 for our site count.

Sunday Surprise #4 – Fillomino (Inequality Clues)

Today’s surprise comes from Hans van Stippent, who sent several creative submissions in for The Art of Puzzles. For this book I’m mostly avoiding “variations”, but I found this puzzle to be a surprising twist perfect for this spot.

Fillomino by Hans van Stippent

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Diagonals

Rules: Variation of standard Fillomino rules. Some clues are not fully specified, and must simply follow the inequality value given in the cell.

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Start with the 2nd row, followed by a comma, followed by the 8th row.

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Sunday Surprise #3 – Spy Futoshiki

Today’s surprise comes from Tyler Hinman, five-time winner of the American Crossword Puzzle Tournament and author of Winner’s Circle Crosswords. I’ve had the pleasure of co-solving with Tyler — whom I call “Kid Crossword” when in “Dr. Sudoku” mode — on many puzzle hunts in recent years and we’ve had a number of good conversations on puzzle design. Total Masyu, which appeared again this Tuesday, for example was an idea that came up in one such chat from Tyler that I constructed for my blog.

As I heard from Tyler a few months ago: “Here’s a weird idea I had the other night while unable to sleep. … It’s inspired by the Spy piece in Stratego, which wins a battle if it attacks the highest-ranked piece (the Marshal), but loses under all other circumstances.” The concept was for Spy Futoshiki, the subject of today’s surprise, where the lowest value (1) is considered greater than the highest value (5), but all other inequalities obey normal ordering. It’s a clever idea and Tyler’s provided a very nice puzzle to demonstrate the change.

Futoshiki Variation by Tyler Hinman

PDF

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

Theme: Spies among us

Rules: Insert a number from 1-5 into each square so that each number appears once in every row and column. Inequality signs between the boxes indicate the larger/smaller numbers, with the single exception that the number 1, the “Spy”, is considered larger than the number 5 if in adjacent cells.

Answer String: Enter the 1st column from top to bottom, followed by a comma, followed by the 5th column from top to bottom.

Solution: PDF

Sunday Surprise #2 – Dalek Invasion

This past week, another doctor made the mistake of appearing here. It seems trouble follows him everywhere, as puzzle creator Craig Kasper reveals here.

Sudoku Variation by Craig Kasper

PDF

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

Theme: Dalek Invasion

Rules: Standard Sudoku rules except that instead of the numbers 1-9 this puzzle uses the letters in “END MATRIX”. Also, clues in the grid represent typical “Seek and Spell/Kanaore” clues; specifically, it must be possible to read each of the words/phrases listed below the grid by starting at the indicated number, moving one cell in the direction indicated by the arrow, and then continuing to move one cell at a time up, down, left, or right to complete the word/phrase. No cell may be used more than once in a single path, but the same cell can appear in the paths of different words/phrases.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 6th row from left to right. Use all capital letters.

Solution: PDF