Return the index of the largest element if it is at least twice as large as every other element. Otherwise return -1.
Example 1
Input: nums = [3,6,1,0]
Output: 1
Explanation: Element 6 is twice as large as 1 and 0.
Output: 1
Explanation: Element 6 is twice as large as 1 and 0.
Example 2
Input: nums = [1,2,3,4]
Output: -1
Explanation: The maximum element 4 is not twice as large as 3.
Output: -1
Explanation: The maximum element 4 is not twice as large as 3.