Given an array of positive integers nums, find the maximum possible sum of a contiguous subarray that forms a palindrome.

An array is considered a palindrome if it reads the same forwards and backwards.

Return the maximum sum among all palindromic contiguous subarrays.

Constraints:

• $1 \leq$ nums.length $\leq 10^5$

• $1 \leq$ nums[i] $\leq 10^9$

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