Puzzle No. 506 & 507: Trio Sudoku, Anti-Diagonal Sudoku [Daily League]

The Trio Sudoku is actually last week’s puzzle. I’d posted it on facebook but hadn’t posted it here. Thats rectified now. Its not the usual Trio Sudoku, but I prefer this slight tweak because it gives more to work with overall.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay. The Anti-Diagonal is today’s offering and will be the one appearing tomorrow on the online solver.

Also, a new puzzle genre I thought of debuted on GM Puzzles this past week. Its called Balance Loop. Have a go at these!

Balance Loop 1.

Balance Loop 2.

Balance Loop 3.

Rules for 506 – Follow regular Sudoku rules. Additionally, Circles must contain only digits 1, 2 and 3. Small squares must contain only digits 4, 5 and 6. Diamonds must contain only digits 7, 8 and 9.

Rules for 507 – Follow regular Sudoku rules. Additionally, each marked diagonal must contain exactly three distinct digits.





WSC/WPC 2014 Recaps: Part VI – WPC Day 2

Day 2 had the rounds with innovative and new puzzles and some rounds with real scoring potential.

Round 8 – English Country Garden (60 minutes) 690/900. 10/12 solved.

This was a round featuring some new styles and some clever representations of old ones, all falling within a theme of objects/animals/etc. found in an English Country Garden. This round featured some big strengths and some bad weaknesses. I don’t know why Cobwebs need to be featured from a garden (edit: I realize they are part of gardens, I just think only the good stuff about gardens should be featured. Or maybe I’m just incredibly biased because I don’t like cobwebby puzzles 😛 Moving on…), but I am really bad at those so I left them for the end and couldn’t get either done. Unfortunately both were high pointers so my score took a hit, even though I started really well with Flowerbeds and Vegetable Plots (Garden!).

Round 9 – Loop The Loop (60 minutes) 670/900. 8/11 solved.

Obviously this was a round full of loop puzzles, both new and known. Overall it was a good mix. Considering I’m good at Loop puzzles this round didn’t go too well. Made a few mistakes, including the Ripple Loop where I spotted the mistake just as they called for time, meaning there was a horrible minute where I was staring at the mistake and couldn’t do anything about it. Ouch.

Round 10 – The 200 Club (90 minutes) 1200/2000. 6/10 solved.

This was my only problem with Day 2 – I don’t like the concept of organizing a round where all puzzles have the same value. I won’t even say the organizers didn’t achieve this as per my experience, because honestly its quite impossible to achieve 10 puzzles of the exact same difficulty. One example where the difficulties definitely did not match for me personally was with the Non Consecutive Kakuro, which had a difficult Global step while the LITS variant was mainly a local solve. Also, a puzzle like Yajilin or LITS variant is much easier to bifurcate and retrace on than something like a 3-in-1 puzzle with multiple constraints. All in all, I just think this could’ve been a perfect round without the same-points theme, and instead just calling it a round with 10 really tough puzzles.

Having said all that, the puzzles were really fun, and the round will be remembered for some of the well built logical steps, and not for the scoring, so the overall experience was still pretty good. Personally, I didn’t do well here because I finished the 6 puzzles I got right within something like 55-60 minutes, and kept breaking puzzles for the next 30-35 minutes. That’s the most frustrating thing to happen with really difficult puzzles, but that’s my own stupidity.

At least it wasn’t as frustrating as something my Swiss friend Fred Stalder did – solving the entire Non-Consecutive Kakuro and then finding out that you’ve switched a 14 sum row and a 20 sum row in an otherwise correct puzzle has got to sting.

Round 11 – Not Quite Classics (60 minutes) 1000/1200. 13/16 solved.

This round contained more extremes than Round 8 in terms of strengths and weaknesses. 5 Tapa variants and a LITS+ meant I pretty much had 6 high-value puzzles (a total of 550 points) in the bag in around 15 minutes. I only wish I wasn’t equally bad at other puzzles as I am good at these. I still think I could’ve done better here since I broke both Diagonal Numberlinks before fixing them. I always get scared of Cross Math puzzles, so I didn’t look at either of them and instead tried and failed to finish a 100 point Tetromino Sums at the end. Maybe I should work on facing my fears.

Round 12 – Something Different (60 minutes) 760/1200. 10/15 solved.

Probably the worst round of the day. This round had one strength (Mini Coral) and everything else was a weakness. I wasn’t expecting much from it, but even so, I would’ve liked to avoid breaking puzzles. Also, I completely forgot about the 140 point Flip Mirror Sums which I feel I could surely have done in the time I spent struggling on each of the two Chaos puzzles. Ah well. At this point all hopes of a top 20 had vanished unless I scored a substantial bonus in Round 13…

Round 13 – Afternoon Tea (45 minutes) 590/670. 7/8 solved.

… and I almost scored a substantial bonus in Round 13. This was a nice round themed around the “T” shape, and all puzzles featured usage of the T-shape in some way. There were two Tapa variants here too which saved a lot of time, giving me 210 points in about 5 minutes. Unfortunately, I don’t know how to spell when the timer is running, as we’ve established from Round 1 in the previous recap. I hit the T for Trees puzzle, which was a mix of Scrabble and the T shape constraint, and in the word list, one of the words was Macadamia. That’s MacadAmia. With an A. I’m emphasizing this, because I entered an E into the grid instead. Now this might not be a big error, and according to Roland Voigt, Will Blatt seems to have received points for misspelled words. However, it just so happens (typically) that this was a crucial letter to mess up. The word Papaya was supposed to connect here with the A. Since it was an E, I had no place for the Papaya and spent a huge chunk of time trying to figure out what was wrong. I noticed the mistake after 10 minutes of staring, time which could’ve been used to finish off the T for Time Tables puzzle quite easily barring any errors.

Round 14 – Doppelgangers (TEAM) (60 minutes) 4740/3600. 19 minutes bonus. 12/12 solved.

Technically, its 6 Doppelgangers solved, but that still makes it 12 puzzles. This was a round having two aspects. First, there were 6 puzzle grids, all of which were solvable using two separate rulesets. Next, these grids were broken into pieces and these pieces were given to us. Participants needed to figure out the relative position of each piece, enter the subsequent clues into the grid on two separate papers, and then solve each puzzle type made by the clues. The doppelgangers were –

Puzzle 1: LITS (240 points) and Star Battle (240 points)
Puzzle 2: Cave (420 points) and Fillomino (300 points)
Puzzle 3: Minesweeper (120 points) and Four Winds (180 points)
Puzzle 4: Masyu (330 points) and Yin Yang (270 points)
Puzzle 5: Nurikabe (330 points) and Numberlink (270 points)
Puzzle 6: Shikaku (220 points) and Cave (680 points)

In this, I took the Cave and Fillomino for starters. This took a while but I got the placement eventually and the solves went pretty quickly as both are strengths. After that, Swaroop gave me his Nurikabe to solve, because he was stuck on it, and had solved the Numberlink correctly. I finished the Nurikabe and by this stage most of the other puzzles were done except the Shikaku and Cave pairing. I’m foggy on whether the Shikaku was finished or not (I roughly remember I did placements for this pairing too, so maybe I solved the Shikaku as well), but the Cave fell to me to finish off, and as the highest pointer, this was pretty difficult. I finished this one with the team waiting and looking on and helping in places. Eventually we ended up with a 19 minute bonus and this felt really good and was a nice end to the day of solving.


This wasn’t the end. After dinner, a recreational team contest was organized by David Bodycombe and his team, just for some light solving after a highly competitive day. This was fun if only because it featured a different kind of puzzle to what we deal with at the WPC. Overall I still prefer grid-based logical pencil puzzles but this was a refreshing change for the evening.

The last recap, maybe even later today, but mostly tomorrow, will deal with the single team round in WPC Day 3, the prize ceremony, etc. I’d like to take this moment to request anyone having photos/videos of Round 15 to send them to me (prasanna16391@gmail.com) so that I can share them and explain the round in a better way.

Puzzle No. 411-414 : UKPC 2013 Puzzles

Edit: Congratulations to Neil Zussman from UK, the overall winner.

Following up from my non-puzzle post before this, I’m still not well folks. And my laptop’s still not fixed. Overall, not a good time. I’m just hoping everything becomes fine by the time the Championships come along.

Speaking of Championships, the UK Puzzle Championship was held recently, around the same time as the IPC. I contributed 4 puzzles to the UKPC. Two of these were fairly common types, Nurikabe and Corral. I had been doing many Kurotto and Yosenabe puzzles around this time, Yosenabe in particular seemed fresh, so I used that and themed a UK into it, adding to my other UK themed puzzle, the Corral. For the other puzzle, I actually wanted to do either a snake variant or a true-false type puzzle. As is usually the cases with me I just ended up combining both and we have True-False Snake.

Anyway, to the puzzles, (with points as they were awarded to each during the UKPC).

P411: Nurikabe. 15 points.

P412: Yosenabe – Move all circles, vertically or horizontally, so they enter the grey areas. Show the movement of a circle by an arrow, with the tip of the arrow in the first cell it enters of its grey area. Arrows can cross through grey areas if they need to reach a grey area beyond. The arrows do not bend, and do not cross other white circles or lines of other arrows. The number in a grey area must be equal to the sum of the numbers of the circles which enter the area. Empty grey areas may have any sum total, but at least one circle must enter each grey area. Example with solution. 20 points.

P413: Corral. 20 points.

P414: True-False Snake – Draw a snake in the grid of unknown length. The head and tail of the snake are given. The body of the snake cannot touch itself, not even diagonally. The numbers indicate the number of cells the snake visits in the direction of the arrow. If the snake does not pass through a clue cell, then that clue is true, otherwise, it is false. Example with solution. 40 points.