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The best masyu site on the internet? Yes! No doubt about it. A generator, a solver, and a daily puzzle? It's almost too much masyu.

The masyu program is written entirely in javascript, no plugins needed! The good thing about writing a slitherlink generator is that it only takes a few interface changes and a some backend logic changes to become a masyu generator!

Check out the iOS app Masyu Infinite
How do I input a solution?
This interface is different than other Masyu programs I have seen. Clicking on a grid-line between two cells will create an input line perpendicular to it. Clicking and dragging a line works, but will sometimes create offshoots when you don't want them.

The generator is really slow.
Yes. Puzzles larger than 20 by 20 are beyond its capabilities almost entirely. Hard puzzles will take much longer to generate. For maximum speed, use Chrome.

What does guess mode do?
It allows you to try a certain line of logic with the ability to clear it out if you get to an invalid position. It's very useful, probably necessary even, on the hard generated puzzles, which use guessing.

When you click on the guess mode button, all the lines and exes you have marked will turn blue, and will not be able to be changed. You can then mess around with the rest of the puzzle. Clicking the clear guess button will remove the lines and exes that aren't blue. Clicking the guess mode button again while still in the mode will turn your marks black again, keeping anything that was there, including any guesses you had.


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