Given an array A of positive integers, A[i] represents the value of the i-th sightseeing spot, and two sightseeing spots i and j have distance j - i between them.
The score of a pair (i < j) of sightseeing spots is (A[i] + A[j] + i - j) : the sum of the values of the sightseeing spots, minus the distance between them.
Return the maximum score of a pair of sightseeing spots.
Example 1:
Input: [8,1,5,2,6]
Output: 11
Explanation: i = 0, j = 2, A[i] + A[j] + i - j = 8 + 5 + 0 - 2 = 11
Note:
2 <= A.length <= 50000
1 <= A[i] <= 1000
class Solution:
    def maxScoreSightseeingPair(self, A: List[int]) -> int:
        res = float('-inf')
        maxleft = float('-inf')
        for i, a in enumerate(A):
            res = max(res, maxleft + a - i)
            maxleft = max(maxleft, a + i)
        return res
class Solution:
    def maxScoreSightseeingPair(self, A: List[int]) -> int:
        res = float('-inf')
        maxleft = float('-inf')
        for i, a in enumerate(A):
            res = max(res, maxleft + a - i)
            maxleft = max(maxleft, a + i)
        return res