<h2><a href="https://leetcode.com/problems/subsets/">78. Subsets</a></h2><h3>Medium</h3><hr><p>Given an integer array <code>nums</code> of <strong>unique</strong> elements, return <em>all possible</em> <span data-keyword="subset"><em>subsets</em></span> <em>(the power set)</em>.</p>

<p>The solution set <strong>must not</strong> contain duplicate subsets. Return the solution in <strong>any order</strong>.</p>

<p>&nbsp;</p>

<p><strong class="example">Example 1:</strong></p>

<pre>

<strong>Input:</strong> nums = [1,2,3]

<strong>Output:</strong> [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]]

</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>

<strong>Input:</strong> nums = [0]

<strong>Output:</strong> [[],[0]]

</pre>

<p>&nbsp;</p>

<p><strong>Constraints:</strong></p>

<ul>

<li><code>1 &lt;= nums.length &lt;= 10</code></li>

<li><code>-10 &lt;= nums[i] &lt;= 10</code></li>

<li>All the numbers of&nbsp;<code>nums</code> are <strong>unique</strong>.</li>

</ul>