okay, so this looks like bullshit
,,, looks at the input
oh, it's time to cheat 
https://codeberg.org/sugar700/advent-of-code-2025/src/branch/master/day12.zig
doesn't work for the example, but this sylveon doesn't care
genuinely curious, is this the intended solution??? fae is under assumption that it probably is, if the author of the puzzle would want to prevent people from cheating, he could do so easily
@rgbunny okay, so the puzzle is about determining whether given shapes fit within a rectangle, the shapes can be flipped, rotated, whatever
this would be really difficult to do, but, there is a trick to the puzzle, for instance, in faer input, the first line is as follows
sugar luna :3 [migrated]
Velvet50x39: 42 56 53 50 49 51
the shapes to fit in the input are respectively made out of: 7, 7, 5, 6, 7, 7 squares
so, let's do the math
42*7 + 56*7 + 53*5 + 50*6 + 49*7 + 51*7 = 1951
50 * 39 = 1950
no matter how optimally the pieces are placed, they won't fit
and when you look through the entire input, every single line in the input either clearly won't fit, or will clearly fit with plenty of room remaining
@sugar Ohhhh
I did figure a quick way to eliminate certain inputs would be to check the sum of the squares, but I figured there could be inputs where the sum would theoretically fit, but the geometry wouldn't allow it.
But if it's giving tons of extra space for the valid inputs, then I suppose it's pretty unlikely for the geometry to prevent it from becoming invalid.
Justin Azoff