# Minimum value of X to make all array elements equal by either decreasing or increasing by X

- Increase any of the array element by
**X**once. - Decrease any of the array element by
**X**once. - If there are 3 unique elements, if
**abs(el2-el1) == abs(el3-el2)**, then the answer is**abs(el2-el1)**. If they are not equal then the answer is -1. - If there are 2 unique elements, the answer is
**(el2 – el1) / 2**, if**el2 – el1**is even, else the answer is (el2 – el1) - If there is a single unique element, then the answer is
**0**

**Time Complexity: **O(N)

**Auxiliary Space: **O(N)

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