Given an array nums, a ramp is a pair (i, j) with i < j and nums[i] <= nums[j]; its width is j - i. Return the maximum width of any ramp, or 0 if none exists. The input is JSON {nums}.
Input: JSON {nums}.
Output: Integer — the maximum ramp width.
Input: {"nums":[6,0,8,2,1,5]}
Output: 4
Explanation: Indices 1 and 5 (0 <= 5).Input: {"nums":[9,8,1,0,1,9,4,0,4,1]}
Output: 7
Explanation: Indices 2 and 9.Input: {"nums":[5]}
Output: 0
Explanation: No pair.1<=n<=5*10^4