Useful math
- Total of permutations for a given array:
n!/(n-k)!wherekis the number of element we are trying to arrange ^082db8 => Permutation of the whole arrayn! - Total number of subset for a given array is
2^n - Combinations:
n!/(n-k)! where k is the number of element we are trying to arrange ^082db8 => Permutation of the whole array n!2^n