enter image description here

You can describe your inversions however you like. I think an ordered grid from the center (n,m) is easy to understand (doesn't matter where to start due to radial symmetry), or an image

  • $\begingroup$ Neat puzzle! Is there a reason why the black regions are not uniform? It's not important, but it makes the puzzle slightly harder to solve using an image editor because it breaks floodfilling. $\endgroup$ – noedne Apr 9 at 21:42
  • $\begingroup$ Because I drew them in procreate. Thats a good point I'll remember that next time I make something like this $\endgroup$ – Artemmm Apr 9 at 21:45

My solution is

2 moves to make the inversions - was very slow to make this horrible graphic! enter image description here

  • $\begingroup$ Correct! Also works with most circles and sections $\endgroup$ – Artemmm Apr 9 at 22:49
  • $\begingroup$ I would have drawn it quicker by making a fresh start with an 8 x 4 rectangular grid. I was able to floodfill the white areas with black but somehow not with black areas with white. $\endgroup$ – Weather Vane Apr 9 at 22:51
  • $\begingroup$ Black areas are shaded. Will make it easier next time. You can see the shading better here m.imgur.com/Sg5RLNi $\endgroup$ – Artemmm Apr 9 at 22:58
  • $\begingroup$ My apologies to @PiIsNot3 because I inadvertently copied his final image, mistaking it for the one in the puzzle. Corrected. $\endgroup$ – Weather Vane Apr 9 at 23:00

EDIT: I found an even better

2 inversion solution:

And of course, this is the optimal solution because you obviously can’t get to the end with only one inversion

Original answer: I can do it in

6 inversions


inverting a set of 4 non-adjacent big triangles (the ones that go BWBW or WBWB), then inverting the 2 black rings that result from that. (Will update with a visual later)

  • $\begingroup$ Correct! Not sure who got it first but both correct $\endgroup$ – Artemmm Apr 9 at 22:51
  • $\begingroup$ @ArtemLugin this was first with the 6 solution, I was working on the graphic for my 2 solution when PilsNot3 announced he had found a 2 solution. However I didn't post anything until mine was ready. $\endgroup$ – Weather Vane Apr 10 at 7:11

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