Algorithm

This problem has already been previously solved using Recursion here:Power Set: Recursion.

To solve it using bit wise operators, we observe a pattern that the number of subsets is dependant on the size of the input array as:

N = 1, No. of subsets = 2
N = 2, No. of subsets = 4
N = 3, No. of subsets = 8 and so on…

No. of subsets of input array of size N = 2N = [1 << n]

Hence we can associate each subset with a number in the range 0 to 2N-1. Each of these numbers represents a bitmask where each bit indicates whether the corresponding element from the input array is included in the current subset or not.

Create an empty array to hold all the subsets of the input array.
Determine the size of the power set, which is 2^N, where N represents the number of elements in the input array.
Iterate through all possible numbers from 0 to 2^N-1: Each number represents a unique combination of elements in the input array.
For each number, generate the corresponding subset.
After constructing each subset, add it to the array of subsets.
Return the array containing all the subsets of the input array.

Code

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