<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>.</p> <p>A <strong>subsequence</strong> of <code>nums</code> having length <code>k</code> and consisting of <strong>indices</strong> <code>i<sub>0</sub> < i<sub>1</sub> < ... < i<sub>k-1</sub></code> is <strong>balanced</strong> if the following holds:</p> <ul> <li><code>nums[i<sub>j</sub>] - nums[i<sub>j-1</sub>] >= i<sub>j</sub> - i<sub>j-1</sub></code>, for every <code>j</code> in the range <code>[1, k - 1]</code>.</li> </ul> <p>A <strong>subsequence</strong> of <code>nums</code> having length <code>1</code> is considered balanced.</p> <p>Return <em>an integer denoting the <strong>maximum</strong> possible <strong>sum of elements</strong> in a <strong>balanced</strong> subsequence of </em><code>nums</code>.</p> <p>A <strong>subsequence</strong> of an array is a new <strong>non-empty</strong> array that is formed from the original array by deleting some (<strong>possibly none</strong>) of the elements without disturbing the relative positions of the remaining elements.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,5,6] <strong>Output:</strong> 14 <strong>Explanation:</strong> In this example, the subsequence [3,5,6] consisting of indices 0, 2, and 3 can be selected. nums[2] - nums[0] >= 2 - 0. nums[3] - nums[2] >= 3 - 2. Hence, it is a balanced subsequence, and its sum is the maximum among the balanced subsequences of nums. The subsequence consisting of indices 1, 2, and 3 is also valid. It can be shown that it is not possible to get a balanced subsequence with a sum greater than 14.</pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,-1,-3,8] <strong>Output:</strong> 13 <strong>Explanation:</strong> In this example, the subsequence [5,8] consisting of indices 0 and 3 can be selected. nums[3] - nums[0] >= 3 - 0. Hence, it is a balanced subsequence, and its sum is the maximum among the balanced subsequences of nums. It can be shown that it is not possible to get a balanced subsequence with a sum greater than 13. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [-2,-1] <strong>Output:</strong> -1 <strong>Explanation:</strong> In this example, the subsequence [-1] can be selected. It is a balanced subsequence, and its sum is the maximum among the balanced subsequences of nums. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= nums.length <= 10<sup>5</sup></code></li> <li><code>-10<sup>9</sup> <= nums[i] <= 10<sup>9</sup></code></li> </ul>