# LC 1695. Maximum Erasure Value ### [Problem link](https://leetcode.com/problems/maximum-erasure-value/) ###### tags: `leedcode` `medium` `c++` `Sliding Window` You are given an array of positive integers <code>nums</code> and want to erase a subarray containing **unique elements** . The **score** you get by erasing the subarray is equal to the **sum** of its elements. Return the **maximum score** you can get by erasing **exactly one** subarray. An array <code>b</code> is called to be a <span class="tex-font-style-it">subarray of <code>a</code> if it forms a contiguous subsequence of <code>a</code>, that is, if it is equal to <code>a[l],a[l+1],...,a[r]</code> for some <code>(l,r)</code>. **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:** - <code>1 <= nums.length <= 10<sup>5</sup></code> - <code>1 <= nums[i] <= 10<sup>4</sup></code> ## Solution 1 - Sliding Window #### C++ ```cpp= class Solution { public: int maximumUniqueSubarray(vector<int>& nums) { unordered_map<int, int> cnt; int windowSum = 0; int ans = 0; int l = 0; for (int r = 0; r < nums.size(); r++) { cnt[nums[r]]++; windowSum += nums[r]; while (cnt[nums[r]] > 1) { cnt[nums[l]]--; windowSum -= nums[l]; l++; } ans = max(ans, windowSum); } return ans; } }; ``` >### Complexity >| | Time Complexity | Space Complexity | >| ----------- | --------------- | ---------------- | >| Solution 1 | O(n) | O(n) | ## Note x