Solution: Next Greater Element IV

Statement

You are given a 0-indexed array of non-negative integers nums. For each element nums[i], determine its second greater element and return an array res where res[i] contains the second greater element of nums[i].

The second greater element of nums[i] is defined as the value nums[j] such that:

• j > i

• nums[j] > nums[i]

• There exists exactly one index k where i < k < j and nums[k] > nums[i]

If no such index j exists, then the second greater element for nums[i] is -1.

Constraints:

• $1\le$ ...