Minimise the maximum difference between the heights

Given an array of integers A representing heights of towers and a positive integer B.
It is allowed to either increase or decrease the height of every tower by B (only once).

Find and return the minimum possible difference between the heights of the longest
and the shortest tower after modifications.

Note: It is mandatory to either increase or decrease the height of every tower.

Input Format

The first argument given is the integer array A.
The second argument given is the integer B.

Output Format

Return the minimum possible difference.

Constraints

2 <= length of the array <= 100000
-10^9 <= A[i] <= 10^9 
1 <= B <= 10^9

For Example

Input 1:
    A = [1, 2, 3, 4, 5]
    B = 2
Output 1:
    3

Input 2:
    A = [5, 17, 100, 11]
    B = 10
Output 2:
    75

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