<p>Given an integer array <code>nums</code> and an integer <code>k</code>, modify the array in the following way:</p> <ul> <li>choose an index <code>i</code> and replace <code>nums[i]</code> with <code>-nums[i]</code>.</li> </ul> <p>You should apply this process exactly <code>k</code> times. You may choose the same index <code>i</code> multiple times.</p> <p>Return <em>the largest possible sum of the array after modifying it in this way</em>.</p> <p> </p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [4,2,3], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> Choose index 1 and nums becomes [4,-2,3]. </pre> <p><strong>Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [3,-1,0,2], k = 3 <strong>Output:</strong> 6 <strong>Explanation:</strong> Choose indices (1, 2, 2) and nums becomes [3,1,0,2]. </pre> <p><strong>Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [2,-3,-1,5,-4], k = 2 <strong>Output:</strong> 13 <strong>Explanation:</strong> Choose indices (1, 4) and nums becomes [2,3,-1,5,4]. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= nums.length <= 10<sup>4</sup></code></li> <li><code>-100 <= nums[i] <= 100</code></li> <li><code>1 <= k <= 10<sup>4</sup></code></li> </ul>