<p>Given a <strong>(0-indexed)</strong> integer array <code>nums</code> and two integers <code>low</code> and <code>high</code>, return <em>the number of <strong>nice pairs</strong></em>.</p> <p>A <strong>nice pair</strong> is a pair <code>(i, j)</code> where <code>0 <= i < j < nums.length</code> and <code>low <= (nums[i] XOR nums[j]) <= high</code>.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [1,4,2,7], low = 2, high = 6 <strong>Output:</strong> 6 <strong>Explanation:</strong> All nice pairs (i, j) are as follows: - (0, 1): nums[0] XOR nums[1] = 5 - (0, 2): nums[0] XOR nums[2] = 3 - (0, 3): nums[0] XOR nums[3] = 6 - (1, 2): nums[1] XOR nums[2] = 6 - (1, 3): nums[1] XOR nums[3] = 3 - (2, 3): nums[2] XOR nums[3] = 5 </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [9,8,4,2,1], low = 5, high = 14 <strong>Output:</strong> 8 <strong>Explanation:</strong> All nice pairs (i, j) are as follows: - (0, 2): nums[0] XOR nums[2] = 13 - (0, 3): nums[0] XOR nums[3] = 11 - (0, 4): nums[0] XOR nums[4] = 8 - (1, 2): nums[1] XOR nums[2] = 12 - (1, 3): nums[1] XOR nums[3] = 10 - (1, 4): nums[1] XOR nums[4] = 9 - (2, 3): nums[2] XOR nums[3] = 6 - (2, 4): nums[2] XOR nums[4] = 5</pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= nums.length <= 2 * 10<sup>4</sup></code></li> <li><code>1 <= nums[i] <= 2 * 10<sup>4</sup></code></li> <li><code>1 <= low <= high <= 2 * 10<sup>4</sup></code></li> </ul>