Light Up
Light up the whole room.
Day closed
A daily puzzle can only be solved on its own day, until 9:00 AM CET the next morning.
3 solvers that day · best: 0:19.57 (Verus)
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- Place light bulbs on white cells so that every white cell is lit.
- A bulb lights its row and column up to the nearest wall.
- No two bulbs may light each other.
- A numbered wall has exactly that many bulbs next to it.
Light Up
What is Light Up?
In Light Up you have to light a dark room. You place bulbs on the white cells, and each bulb lights its row and column up to the nearest wall. The goal is to light every white cell, but no two bulbs may shine on each other. A numbered wall has exactly that many bulbs next to it; walls without a number can have any number of bulbs around them.
The puzzle is known around the world as Akari or Light Up. Start with the sure things: a wall with a 4 has a bulb on all four sides, and no bulb can go next to a 0. Then look for cells that can be lit from only one place. The daily puzzle is 7×7 early in the week and 10×10 on the weekend, and in free play you choose the size yourself.
FAQ
How far does a bulb shine?
In every direction along its own row and column, all the way to the nearest wall or the edge of the board. It lights its own cell too.
What do the numbers on the walls mean?
How many of the wall's four side neighbors hold a bulb. Diagonal neighbors do not count.
Where should I start?
At the walls with a 4 or a 0: the first gets a bulb in all four places around it, the second none at all. Walls with a 3 also give a lot away, especially at the edge of the board.