## Puzzle 373 (Masyu) [Optional Blacks]

This is a Masyu puzzle, with a twist. The loop is not required to pass through black circles. But if a black circle is passed through, it still functions like it would in ordinary Masyu.

Puzzle 373

(Click for larger size)

The gimmick in this puzzle means that trial and error strategies are likely to get you the solution in short order. So I did my best to make the logical path as clean as possible, and I mostly succeeded. For maximum enjoyment and challenge, avoid any if-then sequences of significant depth.

Tags: , , , ,

### 3 Responses to “Puzzle 373 (Masyu) [Optional Blacks]”

1. Scott Handelman Says:

Very fun solve…I was never sure if I was doing what you were asking me to do (that is, I’m not sure how many steps ahead were “allowed”) but it was fun nonetheless.

One minor nitpick: I always solve your puzzles in a Paint-like program, and I naturally wanted to fill in the black circles that were not actually used, but this was hard around the edges because the black circles touched the border. Filling one in would fill them all in. That’s not your fault, though.

• MellowMelon Says:

If you caught a global constraint that led to another break-in in the center besides the bottom white circle, and if you also built on that with a parity argument that allowed you to resolve the direction of the top left white circle after getting the top right, you followed enough for me to be satisfied.

Re the nitpick: I have now updated the images to fix this. Hooray for invisibly different colors/shades that fool the MSPaint flood-fill.

2. David Scherzinger Says:

I actually solved the entire top right corner last (before the rest of the connections fell into place, of course). I couldn’t figure out how to force that white circle in either direction until the end, and everything else built off of that conclusion.

Not one of my favorites, but the center was a nice break-in and the bottom half was a very enjoyable solve.