1685. Sum of Absolute Differences in a Sorted Array.md

Code for ' 1685. Sum of Absolute Differences in a Sorted Array ' (JAVA)

Time: O(n)

Space: O(n)

class Solution {
  public int[] getSumAbsoluteDifferences(int[] nums) {
    final int n = nums.length;
    int[] ans = new int[n];
    int[] prefix = new int[n];
    int[] suffix = new int[n];

    prefix[0] = nums[0];
    for (int i = 1; i < n; ++i)
      prefix[i] = prefix[i - 1] + nums[i];

    suffix[n - 1] = nums[n - 1];
    for (int i = n - 2; i >= 0; --i)
      suffix[i] = suffix[i + 1] + nums[i];

    for (int i = 0; i < nums.length; ++i) {
      final int left = nums[i] * (i + 1) - prefix[i];
      final int right = suffix[i] - nums[i] * (n - i);
      ans[i] = left + right;
    }

    return ans;
  }
}