leetcode 1685 - Sum of Absolute Differences in a Sorted Array

https://leetcode.com/problems/sum-of-absolute-differences-in-a-sorted-array/

You are given an integer array nums sorted in non-decreasing order.

Build and return an integer array result with the same length as nums such that result[i] is equal to the summation of absolute differences between nums[i] and all the other elements in the array.

In other words, result[i] is equal to sum(|nums[i]-nums[j]|) where 0 <= j < nums.length and j != i (0-indexed).

Example 1:

Input: nums = [2,3,5]
Output: [4,3,5]
Explanation: Assuming the arrays are 0-indexed, then
result[0] = |2-2| + |2-3| + |2-5| = 0 + 1 + 3 = 4,
result[1] = |3-2| + |3-3| + |3-5| = 1 + 0 + 2 = 3,
result[2] = |5-2| + |5-3| + |5-5| = 3 + 2 + 0 = 5.
Example 2:

Input: nums = [1,4,6,8,10]
Output: [24,15,13,15,21]

Constraints:

2 <= nums.length <= 10^5
1 <= nums[i] <= nums[i + 1] <= 10^4

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class Solution {
public:
vector<int> getSumAbsoluteDifferences(vector<int>& nums) {
int size = nums.size();
vector<int> result(size, 0);

int sum = 0;
for (int i = 1; i < size; i++) {
sum += i * abs(nums[i] - nums[i-1]);
result[i] = sum;
}

sum = 0;
for (int i = size - 2; i >= 0; i--) {
sum += (size - i - 1) * abs(nums[i] - nums[i+1]);
result[i] += sum;
}

return result;
}
};