Problem 560. Set defaults

Write a function that computes the volume of a cube. The function should be able to accept three inputs: the length, width, and height of a cube. If any of the three inputs are left empty or not given, they should default to value 1.

For example,

computeVolume(2,3,4) 

returns 24, while

computeVolume(2,3)

returns 6, and

computeVolume(1,[],3)

returns 3