This is a three-dimensional Akari puzzle (also known as Light Up). The five squares represent the layers of a $5\times5\times5$ cube, top to bottom. The objective is to add light bulbs into any number of cells so that the resulting grid satifies the following rules:1
- Black cells are walls and cannot contain light bulbs.
- Numbers in black cells indicate how many light bulbs are directly adjacent to that cell (vertically, horizontally or along the Z-axis).
- A light bulb illuminates its own cell as well as every cell visible from it in all six directions (up/down, right/left, and both ways along the Z-axis), continuing until a wall comes in the way.
- Every white square must be illuminated by at least one light bulb.
- No light bulb may be illuminated by another light bulb.
Note: The solution is unique and solvable by logic alone. No guesswork or trial-and-error is necessary here.
1 Paraphrased from the original rules on Nikoli