Time Complexity: O(N2), since we are using two nested for loops to find the next greater elements.

Space Complexity: O(N), The space required to store the answer is O(N).

Optimal Approach

Algorithm

Initialize an answer array with default values of -1
Initialize an empty stack to keep track of elements
Traverse from 2n - 1 down to 0 using modulus to simulate circular indexing
While stack is not empty and top of stack is less than or equal to current element, pop from stack
If index is in the original array range, assign top of stack to answer if stack is not empty, else keep -1
Push the current element onto the stack
After traversal ends, return the answer array