Christmas surprise

[maisie ladybird]

I've received a lovely pressie in the post this morning. Thank you to Gill and Scurra.
Merry Christmas to you all!

[gill216]

Well now we know one has arrived at least.

[Laura]

I've got one too! I'm not supposed to save them till the right month am I? I'm not sure I have that much self-control!!!

[gill216]

Of course you have to save them!

[Scurra]

Yes, well, if I can't get the answer checker working again soon, you'll have to save them.

[giraffe]

Thank you for mine. It was waiting for me when I got in.

[MBH]

Mine was waiting for me at home last night and a lovely surprise it was Thank you.

At first glance those puzzles look 'do-able' - but time will tell. [Yes Scurra, I know they are all 'do-able'..... but!]

[LAT]

At first glance those puzzles look 'do-able' - but time will tell. [Yes Scurra, I know they are all 'do-able'..... but!]

but some are more doable than others?

[Snoopy]

What a lovely surprise in the post this morning! I am not sure where the last few weeks have gone but I hope to have more time soon to settle down and start puzzling again. Thanks to all concerned.

[Wulfruna]

Isn't it great! Well done Scurra on coming up with a new idea .
As we can't print them out online, I suppose we'll have to go back to the photocopier

[MBH]

There are other options to the photocopier

I've recreated the Sudoku in a spreadsheet - added 12 more letters with gusto - - - then ran into a brick wall

I'll get there (eventually).

[Laura]

I got to the same place the sudoku and got stuck. I resorted to a sudoku solver which told me I needed to use X-Wing Strategies. If anyone understands these and can explain them to me some time, I'd be very grateful, cos I always have to go to the sudoku solvers at that point.

[Vladikavkaz]

X Wings...

On a simple basis you have the following possibilities in some cells, either 1 or 2. I've not included other numbers

Code: Select all

1,2|   |   |1,2		
1					
					
1,2			1,2		
					
					

You know that the top left has to be either 1 or 2. The same for all the other corners.
That means that nothing else in the rows or columns can be a 1 or a 2.
So you can get rid of the 1 that's by itself.

[Scurra]

They are called X-Wings because the easiest way to visualise it is to imagine a line connecting the top left and bottom right corners of the "box" since those two squares have to contain the same number, and another line connecting the top right and bottom left (which would then be whatever the other option is, depending upon what the first one turns out to be.) Thus creating a nice X shape. (I believe the "-wing" part may simply be a reference to Star Wars...)

I would consider this to be a moderately advanced strategy; there are much more complicated techniques that cross-reference lots of spaces at the same time but I try to avoid setting puzzles that use anything more than this! And I do try to make sure that when you need to use a trick like this, it will be near the end of the puzzle solve (i.e. when you find it, the remainder of the puzzle will generally fall down like a chain of dominoes.)

But, as ever, I reserve the right to change my mind.

[MBH]

solver which told me I needed to use X-Wing Strategies.

[Totally ignoring Scurra]

OK - I've got my spreadsheet pinned to a ventilation shaft on a Death Star - so how many proton torpedos do we get each?

[Laura]

At least six, I should think!



(Not that I'd know what one was if someone handed me one, but there are some things in life I'm happy enough not knowing about!)

[strep98]

Thanks for mine too, pity I haven't had a chance to look at it properly

[Wulfruna]

Well, it's designed to last all year

[Redfraggle]

I think this is BRILLIANT!!!! Im going to take mine to work - I think I would like to order some more too - i know several people who would appreciate them. Well Pleased