Cat Nap

every cat wants a spot of its own.

seat one cat in every row, column and colour, with no two cats touching

One cat per row, per column and per colour, and no two cats may touch, not even at the corners. Every cat you seat rules out its row, its column, its colour and the eight squares around it, so the board solves itself one forced square at a time: when a colour has one square left, the cat goes there.

Concepts: logic, constraints, deduction.

An interactive you play with one thumb, on Wundr.