Subsets (Power Set)

Given an integer array nums of unique elements, return all possible subsets (the power set).

Example: nums = [1, 2, 3]

• Output: [], [1], [2], [1, 2], [3], [1, 3], [2, 3], [1, 2, 3]

There should be $2^N$ subsets.

We can use the Choose/Not Choose pattern.

For each element in the array, we have exactly two choices:

1. Include it in the current subset.
2. Exclude it from the current subset.

We iterate from index 0 to n. At each index, we branch into these two possibilities.

Watch how the tree expands. Each level represents an index in nums.

Try clicking 'Randomize' to see how the tree changes with different input arrays.