test: 396 solution

py

Author: QuBenhao

problems/problems_396/solution.py

@@ -7,5 +7,14 @@ def solve(self, test_input=None):
         return self.maxRotateFunction(test_input)
 
     def maxRotateFunction(self, nums: List[int]) -> int:
-        pass
-
+        # F(0) = 0 * nums[0] + 1 * nums[1] + 2 * nums[2] + ... (n - 1) * nums[n - 1]
+        # F(1) = F(0) - s + n * nums[0]
+        s = f0 = 0
+        for i, num in enumerate(nums):
+            s += num
+            f0 += i * num
+        ans, n = f0, len(nums)
+        for i in range(1, n):
+            f0 += n * nums[i - 1]  - s
+            ans = max(ans, f0)
+        return ans