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CanvaOA #5

Element Swapping

估计中等评测数据准备中,可先阅读题面

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A software development firm is hiring engineers and used the following challenge in its online test. Given an array arr that contains n integers, the following operation can be performed on it any number of times (possibly zero):

  • Choose any index i (0 ≤ i and swap arr[i] and arr[i + 1]
  • Each element of the array can be swapped at most once during the whole process. The strength of an index i is defined as arr[i] * (i + 1) using 0-based indexing. Find the maximum possible sum of the strengths of all indices after optimal swaps. Mathematically, maximize the following: Function Description Complete the function getMaximumSumOfStrengths in the editor below. getMaximumSumOfStrengths has the following parameter:
  • int arr[n]: the initial array Returns long integer: the maximum possible sum of strengths of all indices after the operations are applied optimally

Constraints

  • 1 ≤ n ≤ 10⁵
  • 1 ≤ arr[i]</cod

Example 1

Input:

arr = [2, 1, 4, 3]

Output:

30

Explanation: It is optimal to swap (arr[2], arr[3]) and (arr[0], arr[1]). The final array is [1, 2, 3, 4], and the sum of strengths = (1 * 1 + 2 * 2 + 3 * 3 + 4 * 4) = 30, which is maximum possible. Thus, the answer is 30.