Patches · strategies
Corners and constraints.
Start with the most constrained cells — size-1 clues and corners — then work inward.
01
Size-1 clues
Any cell with a 1 must be a 1×1 piece. Place them instantly — they wall off their neighbors.
02
Corners and edges
Corner cells can only be covered by pieces that start at or reach the corner. A corner with a size-4 clue must be a 2×2 or 1×4/4×1 touching that corner.
03
Shape exclusion
A cell with a 2-clue must be a 1×2 or 2×1. Look at its neighbors — if one direction is blocked, the other is forced.
04
Fill order
Work from corners and edges inward. Each placement constrains adjacent cells, often forcing their shapes.