<p>You are given an integer array <code>nums</code> where the largest integer is <strong>unique</strong>.</p> <p>Determine whether the largest element in the array is <strong>at least twice</strong> as much as every other number in the array. If it is, return <em>the <strong>index</strong> of the largest element, or return </em><code>-1</code><em> otherwise</em>.</p> <p> </p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [3,6,1,0] <strong>Output:</strong> 1 <strong>Explanation:</strong> 6 is the largest integer. For every other number in the array x, 6 is at least twice as big as x. The index of value 6 is 1, so we return 1. </pre> <p><strong>Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,2,3,4] <strong>Output:</strong> -1 <strong>Explanation:</strong> 4 is less than twice the value of 3, so we return -1.</pre> <p><strong>Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1] <strong>Output:</strong> 0 <strong>Explanation:</strong> 1 is trivially at least twice the value as any other number because there are no other numbers. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= nums.length <= 50</code></li> <li><code>0 <= nums[i] <= 100</code></li> <li>The largest element in <code>nums</code> is unique.</li> </ul>