Binairo Solver
Solve a Binairo (Takuzu) puzzle of 0s and 1s from its given cells.
Binairo, also sold as Takuzu or Binary Puzzle, fills a grid with 0s and 1s under three rules: each row and column holds the same number of 0s and 1s, never three of the same digit sit next to each other, and no two rows are identical and no two columns are identical. Click a cell to cycle it through blank, 0, and 1, then solve.
Click a cell to cycle blank, 0, 1.
How it works
The solver fills the grid one cell at a time, trying 0 then 1. It rejects a choice that would make a third equal digit in a row or column, or that would push a row or column past its half-and-half count, and it checks each completed row and column against the earlier ones so no two match.
Because the rules are strict, a well-formed puzzle with enough givens has a single solution; the solver reports when more than one grid fits.