Kerf Puzzle

Binary puzzle solving techniques

Every Binary puzzle on this site can be solved with the techniques below, without guessing. They run from the easiest to the hardest, and a puzzle's level depends on which of them it needs and how often. The hint button in the game shows these same steps.

No three in a row

Used in: Easy, Medium, Hard

No more than two identical digits may sit side by side. Two 1s next to each other, or two 1s with one empty cell between them, force a 0 into the cell that would make a third. The same holds for 0s.

Example

Half and half

Used in: Easy, Medium, Hard

Every row and every column holds as many 1s as 0s. Once a line has its full share of one digit, every empty cell left in it takes the other digit.

Example

Only one way

Used in: Medium, Hard

When a line has only a few empty cells left, list the ways to fill them that keep the counts even and never put three alike side by side. If only one way works, write it in.

Example

No twin lines

Used in: Hard

No two rows may be the same, and no two columns. When a line can still be finished in two ways and one of them would copy a line that is already complete, the other way is the answer.

Example

Play Binary

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