Given an array A of integers, for each integer A[i] we need to choose either x = -K or x = K, and add x to A[i] (only once).

After this process, we have some array B.

Return the smallest possible difference between the maximum value of B and the minimum value of B.

 

Example 1:
```
Input: A = [1], K = 0
Output: 0
Explanation: B = [1]
```
Example 2:
```
Input: A = [0,10], K = 2
Output: 6
Explanation: B = [2,8]
```
Example 3:
```
Input: A = [1,3,6], K = 3
Output: 3
Explanation: B = [4,6,3]
```
 

Note:

    1 <= A.length <= 10000
    0 <= A[i] <= 10000
    0 <= K <= 10000