<p>There is an integer array <code>nums</code> sorted in ascending order (with <strong>distinct</strong> values).</p> <p>Prior to being passed to your function, <code>nums</code> is <strong>possibly rotated</strong> at an unknown pivot index <code>k</code> (<code>1 <= k < nums.length</code>) such that the resulting array is <code>[nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]]</code> (<strong>0-indexed</strong>). For example, <code>[0,1,2,4,5,6,7]</code> might be rotated at pivot index <code>3</code> and become <code>[4,5,6,7,0,1,2]</code>.</p> <p>Given the array <code>nums</code> <strong>after</strong> the possible rotation and an integer <code>target</code>, return <em>the index of </em><code>target</code><em> if it is in </em><code>nums</code><em>, or </em><code>-1</code><em> if it is not in </em><code>nums</code>.</p> <p>You must write an algorithm with <code>O(log n)</code> runtime complexity.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre><strong>Input:</strong> nums = [4,5,6,7,0,1,2], target = 0 <strong>Output:</strong> 4 </pre><p><strong class="example">Example 2:</strong></p> <pre><strong>Input:</strong> nums = [4,5,6,7,0,1,2], target = 3 <strong>Output:</strong> -1 </pre><p><strong class="example">Example 3:</strong></p> <pre><strong>Input:</strong> nums = [1], target = 0 <strong>Output:</strong> -1 </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= nums.length <= 5000</code></li> <li><code>-10<sup>4</sup> <= nums[i] <= 10<sup>4</sup></code></li> <li>All values of <code>nums</code> are <strong>unique</strong>.</li> <li><code>nums</code> is an ascending array that is possibly rotated.</li> <li><code>-10<sup>4</sup> <= target <= 10<sup>4</sup></code></li> </ul>