On Your Marks…

Before you dash off towards the Nikoli Hurdles let’s familiarize ourselves with the Answer Keys. This is what you need to extract from each puzzle’s solution.


4 squares in the puzzle will be marked with A, B, C and D. Use the given keys to describe the content of the 4 cells. In shading puzzles, B and W denote a shaded and unshaded cell. In loop puzzles, numbers 1-6 show the possible configurations of the loop segment in that cell. Cells in number-filling puzzles can be represented by that particular number itself. For two digit numbers, only use the digit in the ones column.

Using this notation, each answer key should end up being a 4-digit number. (With B and W in some cases).

More details coming soon!

Announcing Puzzle MAT

First off, my Bookshelf tab is migrating. I have been wanting to do something with my book reviews for a while. After a few days of tweaking here and there, my Puzzle MAT site is now up and running. I will pop in every Tuesday to review a puzzle book with more details than you’d usually see in their official sites. I cater the cruciverbalists as well so expect the occasional word-play puzzle books.

Competition-wise, things have been running very slowly here. Now that I’ve got the solutions of the 1st Code Road out of the way, its time to announce the next event!

hurdles preview

What better time to reorganize book reviews and run a competition than early 2013?

Solutions to 1st Code Road – Part 3/3

Puzzle 4 – Masterpiece

After piecing together the pictures you’d be left with finding something completed in 1507 and was first housed in the Prague Castle.

prague castle

But now it’s in the Musel de Prado.


The Prado houses fine arts and the title “Masterpiece” should point to something of that matter. So the 10 letter painting, by Albrecht Durer, titled “ADAM AND EVE became our answer.


Puzzle 5: Septet

The MSN smileys represent names of the Seven Dwarfs. They all interlock in the given grid; Happy, Grumpy, Bashful, Sleepy can be inferred by the emoticons. Doc wears glasses, Dopey doesn’t talk much and Sneezy is supposedly ill.



The 9 letter answer is SNOWWHITE

And lastly, Puzzle 6 – Inner Core

IPAD, NEWTON, WILLIAM TELL, ADAM AND EVE and SNOWWHITE share a common link with the APPLE. If the link isn’t clear enough, the title ‘Inner Core’ should’ve suggested this fruit either way around.


Construction Notes:

Puzzle 5 is one of those puzzles where if you know how it works the whole thing falls but if you have no idea then you can’t even make a start. I stared at the end result blankly several times questioning its usability. Heck. The title “Septet” shouldn’t make it too hard, and into the Code Road it went.

I was hooked on the Google A Day trivia game so I originally planned Code Road to be a set of 5 questions. Puzzle 4 wrote itself: What 1507 painting was first housed in the Prague Castle and now on display at the Prado?

4-5 more and I’ll have a little contest in no time, right? I even brainstormed some short puzzles and name the contest: Quizzle, a combination of quiz and puzzle. However, a quick Google search later and I have to find a replacement name. Quizzle is apparently a quite large firm helping out with financial supports.

Code Road was actually a little game I concocted at high school during classes. It was a run of 4 puzzles played by 8 people and each round eliminates 2 people. It killed time and had to be done under radar while the teacher monitors the students.

Solutions to 1st Code Road – Part 2/3

Puzzle 3 – Sum Thing Happened


The Killer Sudoku was probably the hardest puzzle in Code Road. First off lets solve the sudoku:

cd1ans4bThe given 0, 1 and 2 restricts the possibly of the 8-cage to 0, 1, 3 and 4. This further forces the content of the 12-cage to 5 and 7. More contents of 2-cell cages can be determined but not yet placed in the centre-bottom nonet. The 3-cell cage adding to 4 has to contain 0, 1 and 3 only.


The 15-cage has be to maximally filled with 7 and 8, so the placement on the 12-cage can be determined. The central horizontal row can now be filled using the content of the 8-cage in the central-right hand side nonet. The 22-cage can be filled with either 6, 8, 8 or 7, 7, 8 – but since the determined 1, 7 filling the 8-cage – leaves only one possible placement of 6, 8 and 8.


More progress can be made looking at the 3rd column, the top 6-cage has to contain 1 and 5. The bottom-left nonet can also be marked. Using basic sudoku rules and the key placements in the vertical 9-cage and the 17-cage, the entire left hand side of the puzzle can be fully mapped.


The 7th row can be mapped using the remaining 3 numbers, the 1 has to go to the 14-cage to satisfy the 8-cage. The 7-cage in the top right nonet is left with 3 and 4. The 0 forces the neighbouring cell to be a 5, which makes more progress in the top left corner. From here, try to remind yourself to revisit the sudoku rules. This should open the 6th column and clear the top-centre nonet.

The last 10 or so cells are now a piece of cake.


After you’ve solved the Killer Sudoku using numbers 0-8. The shaded squares read out a date. Which was 18/11/1307. According to the Swiss folklore, it is the day that William Tell famously shot an apple from his son’s head. The 11 letter answer is WILLIAMTELL.

Construction Notes: Because the solution date had a zero, a sudoku wasn’t possible so I originally have in mind, a Number Crossword. Think a crossword where the clues are something like [23 Across: 392+956], [13 Down: Number of rings in the Olympics logo + Days in July], [6 Across: A prime number] etc. A run of eight digits would be shaded to reveal the date of 18/11/1307.

When I opened up Excel, drew a grid and start filling in entries I thought, “Man. This is boring.” It would be a crime to put my own readers to that much boredom so I quickly scrapped the idea for something else.

The Killer Sudoku was actually one of many puzzles from my puzzle shed (a place where unused puzzles made with no clear intention slowly pile up). The original puzzle was 1-9 but since the date contained a zero every digit was subtracted by 1 and every cage was subtracted by the number of cells it contained.

Test solved it 3 times because puzzles from my puzzle shed aren’t thoroughly checked like ones I write for planned occasions. The puzzle works. Hooray. Into Code Road it went.

Solutions to 1st Code Road – Part 1/3


Puzzle 1: At Your Fingertips

The first puzzle was clearly a word search. There is no wordlist but there were pictures splashing around the grid. A quick scan should quickly allow you to infer that these form the wordlist. Going from left to right the words represented are CALCULATOR, MUSIC NOTE, SUNFLOWER, CALENDAR, MAILBOX, CLOCK, PHONE, CLOUD, CAMERA, COMPASS and GEAR.

Once you’ve crossed them all off the grid, the leftover letters spell out:


“Our most advanced technology in a magical and revolutionary device”, which is a part of what Steve Jobs said at the launching of the IPAD in January 2010.

Hints: The title “At Your Fingertips” should indicate a touch-screen device. Not sure if many people realize this, but the pictures that form the word list are ones that are commonly found as icons in Apple’s menu:



Puzzle 2: It All Weighs Out


The two men are Blaise Pascal and Jonas Angstrom. Both men lend their names to metric units, namely; the Pascal (Pa) and the Angstrom (A.). Pascal is a unit of force and 1 pascal is equal to 1 newton over a metre-squared. Angstrom is a unit of length and 10 to the 10 angstroms equals one metre.

So the missing face is that of Isaac NEWTON and his 6 letter surname is our answer.


Construction Notes:

The first puzzle plays many roles, most importantly: hooking attention. With so many puzzles out there, one is unlikely to continue if the first impression is bland. Originally the first puzzle was the Killer Sudoku (puzzle 3). On second thought, it might intimidate non-logic puzzle solvers and scare them away; whereas a simple word search is self-explanatory and something you can instantly sink your teeth in.

NEWTON was on my things-to-do-with-apple list and he has to be an answer to some sort of puzzle. I knew that Newton was a unit of force and so was Pascal. I was unsatisfied with the equation that hasn’t included Angstrom in and thought of a way to get rid of the ‘metre’ and find someone who is also a unit of length. My first thought was Angstrom and all I knew was an Angstrom is very tiny. What I learnt was that an Angstrom is conveniently 1 over 10^10 metres and Puzzle 2 was born.