[peterpuzzle]

Creator here. No, you can arrange the puzzle pieces to make dates that don't exist, like Monday February 31. Actually there may be "impossible" dates, because I didn't check for them, but I guess all combinations of days of the week, day of the month and month are possible. And also many non-dates, like 1, 2, 3. But good point: alle possible dates have at least 1 solution. Disclaimer: I sell these puzzles for a little more than the raw material.

[slig]

So nice! Do you create them entirely algorithmically, or do you use the solver just to verify that every date is possible?

[peterpuzzle]

I wrote 2 solvers in Python. One that loops through all possible dates and searches for a solution. And one that loops through all solutions and checks if they form a date or not. And luckily both gave the same answers.

[drivebyhooting]

How did you select the piece shapes to ensure there was always a solution?

[peterpuzzle]

Actually I tried a lot of different combinations of piece shapes to find the "hardest" set of pieces that can still solve all possible dates. "Hard" is subjective, but I mean pieces with multiple protrusions.

[seanhunter]

Looks like a really nice puzzle. Congrats.

[legedemon]

Great puzzle. Do you ship internationally?

[yapyap]

not OP but yes