You have three tasks, all of which need to be completed.

First, you can complete any one task at cost 0.

Then, just after completing the i-th task, you can complete the j-th task at cost |A_j - A_i|.

Here, |x| denotes the absolute value of x.

Find the minimum total cost required to complete all the task.

Constraints

• All values in input are integers.
• $1 \leq A_1, A_2, A_3 \leq 100$

Input

Input is given from Standard Input in the following format:

A_1 A_2 A_3

Output

Print the minimum total cost required to complete all the task.

Examples

Input

1 6 3

Output

5

Input

11 5 5

Output

6

Input

100 100 100

Output

0

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