Hacker News Reader

Comment by donatj | Hacker News Reader

It seems like there's a simpler, lazier solution to having a puzzle with just two solutions.

Just make two corners diagonal from each other interchangeable, then simply print "this side up" on one of the corner pieces and have the image be a rotational illusion that look like different items when rotated 180°

View on HN

And in the video Matt talks about the effort he went to in order to avoid trivial solutions like that. He wanted to find the least trivial one he could.

Or don't print an image at all, leave it a solid color, and then you have four solutions - two landscape, two portrait - if you leave yourself restricted to 90° angles.

(Technically eight, if you also flip the puzzle upside down.)

Trivial solutions aren't interesting solutions.

Or just flip over a normal jigsaw and give yourself a challenge.

Long before this Matt video, I've done just that. A generator of devilish no-image jigsaw puzzles :-) which I indeed wanted to do a little Show HN someday. I made a small python script call a SAT solver to create a MxN puzzle with only 1 solution but only a few jig shapes, so maaany 'almost solutions'. Then I laser cut a plastic board and made it real, and gave one copy to a friend. At least a nice use of SAT solvers that is more efficient than Matts brute force approach.

Yes please, show your script!

The most recent one I did had a grid of letters on the back, to make sure things align. I wonder if that would make it easier or harder to solve than if it were a single color

There's a jigsaw brand (impossipuzzle, I think) that does something like that to make them as difficult as possible. They're printed on both sides, and the rows/columns are cut from different sides.

I have aunts that took almost a year solving one that was an 5*7 foot picture of baked beans and chips. Most of the patterns are repetitive and non-distinct on purpose.

What do you do with such a monstrosity when it's finished?

They glued it to a sheet of plywood and hung it on the wall.

Reply on news.ycombinator.com