LeetCode 1695. Maximum Erasure Value

Author: raul-sauco

README.md

@@ -26,6 +26,7 @@ Proposed solutions to some LeetCode problems. The first column links to the prob
 | [1461. Check If a String Contains All Binary Codes of Size K][lc1461] | Medium     | [python](leetcode/has_all_codes.py)                                  |
 | [1480. Running Sum of 1d Array][lc1480]                               | Easy       | [python](leetcode/running_sum.py)                                    |
 | [1658. Minimum Operations to Reduce X to Zero][lc1658]                | Medium     | [python](leetcode/minimum-operations-to-reduce-x-to-zero.py)         |
+| [1695. Maximum Erasure Value][lc1695]                                 | Medium     | [python](leetcode/maximum-erasure-value.py)                          |
 
 [lc1]: https://leetcode.com/problems/two-sum/
 [lc3]: https://leetcode.com/problems/longest-substring-without-repeating-characters/
@@ -44,3 +45,4 @@ Proposed solutions to some LeetCode problems. The first column links to the prob
 [lc1461]: https://leetcode.com/problems/check-if-a-string-contains-all-binary-codes-of-size-k/
 [lc1480]: https://leetcode.com/problems/running-sum-of-1d-array/
 [lc1658]: https://leetcode.com/problems/minimum-operations-to-reduce-x-to-zero/
+[lc1695]: https://leetcode.com/problems/maximum-erasure-value/

leetcode/maximum-erasure-value.py

@@ -0,0 +1,41 @@
+# https://leetcode.com/problems/maximum-erasure-value/
+from typing import List
+
+
+class Solution:
+    def maximumUniqueSubarray(self, nums: List[int]) -> int:
+        seen = {}
+        sum = 0
+        left = 0
+        max_sum = 0
+        for right in range(len(nums)):
+            if nums[right] in seen:
+                # Move the left pointer to the left of the last seen position removing the values from the sum
+                while left <= seen[nums[right]]:
+                    sum -= nums[left]
+                    left += 1
+
+            # Always add the new, or updated, seen position and the value to the sum
+            seen[nums[right]] = right
+            sum += nums[right]
+            max_sum = max(max_sum, sum)
+
+        return max_sum
+
+
+tests = [
+    [[4, 2, 4, 5, 6], 17],
+    [[5, 2, 1, 2, 5, 2, 1, 2, 5], 8],
+    [[1], 1],
+    [[10000, 1, 10000, 1, 1, 1, 1, 1, 1], 10001]
+]
+
+
+def test():
+    sol = Solution()
+    for t in tests:
+        result = sol.maximumUniqueSubarray(t[0])
+        assert result == t[1], f'{result} != {t[1]}'
+
+
+test()