1. Each cell contains 0 or 1.
2. No Trio Rule: Three 0s or three 1s are not allowed (vertically and horizontally).
3. Balanced Digit Rule: Each row and column contains an equal number of 0s and 1s.
4. Uniqueness Rule: Each row is unique among rows. Each column is unique among columns.
Together, these rules can be used step-by-step to solve the entire grid.
The following examples are parts of a full grid.
Hover over or tap the examples to see how they can be filled in.
"..." indicates cells that do not affect the outcome.
It may be necessary to "look ahead" to find the next digit (not to be confused with guessing and checking, which should never be required!)