This 'diabolical' game took me 3 hours to complete on a humid and hot Sunday afternoon in my house attic. The difficulty of the game ratings given by the Daily Telegraph depend on the day of the week each game in played.
Monday is 'Gentle' or easy Beginner level. Tuesday and Wednesday is 'Moderate' for Intermediate, Thursdays are 'Tough', Friday and Sundays are 'Diabolical' meaning next to impossible or Gamer Advanced and Saturdays are 'Moderate'
I've been a fan of the Japanese puzzle game for almost 10 years now, I believe. Sudoku is the innocuous looking 9 square puzzle where there are numbers from 1 - 9. There is no number zero used in this game.
Rule of the Game
The objective of this game is simple. In the 9 squares, the player must fill in each row and each column ONLY ONCE the number 1 to 9. There cannot be a repeat of the number on any row or column. In addition, each outlined box can only have the number 1 to 9 appearing only once !
Tricks and Tips
Unless you are very experienced and clever, I would advise to print out the game, and write the possibilities of that number coming out in the square - for the diabolical or very difficult levels.
a) Print Out the Puzzle
Write out all the possibilities inside the small square for easy recollection and deduction later in the game.
b) Use the elimination level method to fill in the empty square.
If for example the 2 9 x 9 squares have the same number which are above and below that of the empty square when extrapolated, then there is the high possibility that square will show up that number. (Its very hard to explain in writing).
c) When a square within the box has the same 2 numbers, they are 'booked' meaning
This means that within the 9 square box, these 2 squares can only have these 2 numbers, hence by logical deduction, the remaining 7 other numbers need to be filled either within the 9x9 square, the column or row
e) Count each line and column to ensure there is only 1 number between 1 to 9
This is the hardest thing for me to do. There are so many lines and columns (9+9 or 18), so it tries my focus thinking to the maximum and this is where I reap the greatest benefit, I can easily spend 1 - 3 hours (not continuously but with breaks in between) on a game, but normally most times I can finish the most difficult sudokus within 30 minutes PROVIDED
> my mind is clear and focussed
> I have had a good sleep the night before
> I have no other distractions
d) Gwendolin's Thread
Finally, when all else fails, when I have deduced and eliminated all the other possibilities and put in all the 'given' or confirmed numbers, I am left with a puzzle where there are about 10 - 20 possibles and the rest are 100% givens and filled in, I will do what Princess Gwendolin did, 'guess' (either a 50 /50)
and circle the possible number at the top corer of the square and try to finish it. There will be a 'thread' or a path where I can backtrack using the 'string' I had placed for myself especially if the path turns out to be wrong one. I do not want to be going in circles and coming to a dead end and encountering 2 number 9s along the same row or column.
So, if along the way, I find there are (for example) 2 number 8s along the same row or column, then I will need to backtrack to where I first made that guess.
It is obviously the wrong route, so I will erase my error, and start back to the original point where I chose one number out of two (a 50 / 50). I will then proceed to take the other number and proceed on from there.
Normally I will be able to finish the game this way.
So that's it folks
Sudoku Game De Mystified !
Have Fun Playing ! You only challenge yourself on time and patience.
Becoming a Top Level Player is not difficult.