題目如下：

You are given an array of positive integersnumsand want to erase a subarray containingunique elements. Thescoreyou get by erasing the subarray is equal to thesumof its elements.

Returnthemaximum scoreyou can get by erasingexactly onesubarray.

An arraybis called to be asubarrayofaif it forms a contiguous subsequence ofa

, that is, if it is equal toa[l],a[l+1],...,a[r]for some(l,r).

Example 1:

Input: nums = [4,2,4,5,6]
Output: 17
Explanation: The optimal subarray here is [2,4,5,6].

Example 2:

Input: nums = [5,2,1,2,5,2,1,2,5]
Output: 8
Explanation: The optimal subarray here is [5,2,1] or [1,2,5].

Constraints:

• 1 <= nums.length <= 105
• 1 <= nums[i] <= 104

解題思路：滑動視窗問題。從左往右依次遍歷nums，並用字典儲存出現的元素以及計算出這些元素的和。如果當前遍歷到對應元素已經出現過，則在字典中刪除最左邊元素。

程式碼如下：

class Solution(object):
    def maximumUniqueSubarray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        left = 0
        right = 0
        dic 
 
= {}
        res = 0
        amount = 0
        while right < len(nums):
            if nums[right] not in dic:
                dic[nums[right]] = 1
                amount += nums[right]
                right += 1
                res = max(res,amount)
            else:
                amount -= nums[left]
                del dic[nums[left]]
                left += 1
        return res