Championship Chatter – Final Puzzles and Thoughts

Here are the final puzzles from the US Sudoku Qualifying Test that I wrote. Both are less common types. Tomorrow will finally bring some new puzzles, and I hope some surprises too.

The first of this set, a “Seek-and-Spell” variant, is a style that took on a life of its own on this website a few months ago as more and more constructors kept submitting it. I wanted a very United States sort of puzzle somewhere on this test and found a good letter set to get 5 states into this grid. I wanted OHIO from the start as an easy Seek-and-Spell rule placement. But the value of states like MONTANA and INDIANA became clear during construction. This may have been the only case on the test where some non-sudoku logic puzzling skill would really accelerate the solve as the Seek-and-Spell placements are quite limited and getting them fixed makes the rest much easier.

The second of this set is a style I first created for a Czech/US Sudoku Championship several years ago and one that I keep bringing out every year typically for championship season. It is one of the easier styles construction-wise to get started with creative themes as it does not take a lot of digits in either grid before the linked cells really start to force the solve. But occasionally getting both grids to behave by the end can be hard. Here, my seeds were two different styles of basic step in the two grids. And after finding the linked regions, consistently ping-ponging between the two puzzles to get to the end. It is another of my favorites on this test.

Not posted this week were the great submissions from Wei-Hwa Huang. This year I gave him a sketch of the styles I wanted and he delivered in a large way. For example, I had a basic concept to play with Binary in a 6×6 grid with missing digits much like the Indian GP test had a play on this with Braille. Wei-Hwa took it farther than I did though with 0-7 and three bits being a perfect choice and his example and test puzzle were both quite fun. The Property Sudoku also had quite an elegant solve and his Diagonal had a good, but fair, challenge.

Sudoku by Thomas Snyder

PDF

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

Theme: United States

Rules: Standard Sudoku rules except that instead of the numbers 1-9 this puzzle uses the letters ADEHIMNOT. 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: For the USSQT, the answer strings were a set of rows/columns encountered late in the puzzle. For this week, you can just hit the solved button on an honor system if you think you’ve solved it.

Solution: PDF

Sudoku by Thomas Snyder

PDF

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

Theme: Logical

Rules: Standard Sudoku rules for each of the two grids. There are three shaded regions in each grid. The shaded regions must exactly match between the puzzles, but which shaded regions correspond to which must be discovered.

Answer String: For the USSQT, the answer strings were a set of rows/columns encountered late in the puzzle. 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

Dr. Sudoku Prescribes #98 – Sudoku (Skyscraper)

Sudoku (Skyscraper) by Thomas Snyder

PDF

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

This is a “Twisted Tuesday” puzzle variation.

Theme: Big City

Rules: Standard Sudoku rules. Also, standard Skyscrapers rules.

Answer String: Enter the 8th column from top to bottom, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 6:30, Expert = 13:00

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

From the Foxger’s Den #13: Sudoku (Seek and Spell)

Sudoku Variation by Grant Fikes

PDF

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

This is a “Twisted Tuesday” puzzle variation.

Theme: Doctor Sudo-Who?

Rules: Standard Sudoku rules except that instead of the numbers 1-9 this puzzle uses the letters in “WORD BATCH”. 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 1st column from top to bottom, followed by a comma, followed by the 5th column from top to bottom. Use all capital letters.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 7:00, Expert = 14:00

Solution: PDF

Dr. Sudoku Prescribes #62 – Sudoku (Seek and Spell)

Sudoku Variation by Thomas Snyder

PDF

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

This is a “Franken-Friday” puzzle variation.

Theme: Mostly Themeless! – Besides elements of symmetry and some patterning in the numbers, the design is focused on the logical solution path.

Rules: Standard Sudoku rules. Clues in the grid represent typical “Seek and Spell/Kanaore” clues; specifically, it must be possible to read each of the numbers listed below the grid by starting at the indicated letter, 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 number. No cell may be used more than once in a single number’s path, but the same cell can appear in the paths of different numbers.

Answer String: Enter the 3rd column from top to bottom, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 12:30, Expert = 25:00

Solution: PDF

Welcome to Grandmaster Puzzles!

A logo, and a puzzle

PDF

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

Welcome to the new puzzle blog from Thomas Snyder, aka “Dr. Sudoku”, 3-time world sudoku champion and author of many books of puzzles including “The Art of Sudoku”. Here you will find a range of logic puzzles including number placement puzzles (such as Sudoku and TomTom), object placement (such as Battleships and Star Battle), region division (such as Fillomino and Cave), shading (such as Nurikabe and Tapa), path/loop (such as Slitherlink and Masyu) and many more.

Puzzles will get progressively harder throughout the week, so there will be easy puzzles for beginners on Monday and Tuesday to start the week and much harder puzzles by Friday and Saturday. Eventually there will be a random mix of many puzzle types every week, but as I start I will focus on two types each week, with Sudoku and TomTom leading the way. Puzzles will typically post at 9:00 AM Pacific Time.

This puzzle blog will have a few unique features. First, I want to actively track (and reward) the puzzle solvers. At the bottom of each post is a “solved” button. If you enter the correct answer string, your solution will be logged in. Eventually there will be leaderboards, contests, and prizes for people solving the puzzles. So if you solve the puzzles, log your success here. Mark your favorite puzzles too. So if a lot of solvers for example like TomTom over other styles, then you’ll see more of them here — and more TomTom books published.

Each puzzle has a “difficulty” posted too. This is just a recommendation from the expert/World Puzzle Championship level solvers who have helped test all the puzzles. The time has three values: the “Master” time, and then an “Expert” time (3x) and a “Novice” time (10x). Whatever level solver you are, these ratings should give you a sense of how hard a puzzle might be, and also give you a real sense of how well you are solving if you want to time yourself. But don’t start the stopwatch if you are just here for fun!

For any puzzle you really like, click on the tags to the left for more examples. Besides the posted puzzles, I will be releasing books with all of these puzzle styles. For Sudoku and Sudoku Variations and TomTom I already have books available for purchase. For the other styles, new titles like “The Art of Puzzles” will be coming soon.

This will be an exciting project, and I hope to see you visiting here a lot in the future. And if you have any recommendations for new puzzle styles, or want to make your own puzzle contributions here, just email me to start a dialogue.

Rules: The puzzle in this post is in the GMPuzzles logo. This is a Wordoku with a repeated letter so follow standard sudoku rules with a slight twist.

Time Standard: Sudoku Master = 2:30, Expert = 7:30, Novice = 25:00

Answer Check: USING CAPITAL LETTERS, enter the 8th row from left to right, followed by a comma, and then the 5th column from top to bottom (e.g. “GMPUZZLES,GMPUZZLES”)

Solution: PDF