3496. Maximize Score After Pair Deletions

You are given an array of integers nums. You must repeatedly perform one of the following operations while the array has more than two elements:

• Remove the first two elements.
• Remove the last two elements.
• Remove the first and last element.

For each operation, add the sum of the removed elements to your total score.

Return the maximum possible score you can achieve.

class Solution {
public:
    int maxScore(vector<int>& nums) {
        int n = nums.size(), remain = nums.size() % 2 ? 1 : 2;
        int sum = accumulate(begin(nums), end(nums), 0), res = INT_MIN;
        for(int i = 0; i <= n - remain; i++) {
            int sub = accumulate(begin(nums) + i, begin(nums) + i + remain, 0);
            res = max(res, sum - sub);
        }
        return res;
    }
};