115. Maximum Sum Circular Subarray

Medium · Array

Given a circular array of integers, find the maximum possible sum of a non-empty contiguous subarray. Because the array is circular, a subarray may wrap around from the end back to the beginning, but each element may be used at most once.

The input is the array. Return a single integer — the maximum circular subarray sum.

Examples

Example 1
Input: [1,-2,3,-2]
Output: 3
Explanation: Subarray [3] gives the largest sum.
Example 2
Input: [5,-3,5]
Output: 10
Explanation: Wrapping around: [5] + [5] = 10.

Constraints