Light Up
Place light bulbs to illuminate every white cell without any two shining on each other.
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How to play
- Place light bulbs in white cells to illuminate the entire grid.
- Each bulb shines light horizontally and vertically until blocked by a black cell or the grid edge.
- No two bulbs may shine on each other (they cannot share a row or column without a black cell between them).
- A number on a black cell shows how many bulbs must be placed in orthogonally adjacent white cells.
- Unnumbered black cells can have any number of adjacent bulbs.
Illumination & Light Rays
Each light bulb shines light horizontally and vertically until blocked by a black cell or the grid edge. Every white cell must be illuminated.
No Mutual Illumination (Bulb Conflicts)
No two light bulbs may shine on each other. Two bulbs cannot share a row or column unless there is a black wall between them.
Numbered Black Cells
A number on a black cell indicates the exact count of light bulbs in its orthogonally adjacent white cells. Unnumbered black cells have no count restriction.
Light Up
How to play Light Up
- Place light bulbs in white cells to illuminate the entire grid.
- Each bulb shines light horizontally and vertically until blocked by a black cell or the grid edge.
- No two bulbs may shine on each other (they cannot share a row or column without a black cell between them).
- A number on a black cell shows how many bulbs must be placed in orthogonally adjacent white cells.
- Unnumbered black cells can have any number of adjacent bulbs.
Illumination & Light Rays
Each light bulb shines light horizontally and vertically until blocked by a black cell or the grid edge. Every white cell must be illuminated.
No Mutual Illumination (Bulb Conflicts)
No two light bulbs may shine on each other. Two bulbs cannot share a row or column unless there is a black wall between them.
Numbered Black Cells
A number on a black cell indicates the exact count of light bulbs in its orthogonally adjacent white cells. Unnumbered black cells have no count restriction.
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