You are painting the four walls of a rectangular room (not the floor or ceiling). The room is length by width metres and height metres tall. One can of paint covers coverage square metres. Write paint_cans(length, width, height, coverage) that returns the number of whole cans you must buy.
Examples
Input: length = 5, width = 4, height = 3, coverage = 10
Output: 6
Explanation: walls total 2 * (5 + 4) * 3 = 54 m²; 54 / 10 = 5.4, so 6 cans.
Input: length = 5, width = 4, height = 3, coverage = 54
Output: 1
Constraints
- All values are positive ints or floats, at most
1000 - Return an integer
Goals
- Compute the area of four walls
- Round up to a whole number of cans