Problem Statement

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.

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.

Constraints

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

Sample Input 1

1 6 3

Sample Output 1

5

When the tasks are completed in the following order, the total cost will be 5, which is the minimum:

• Complete the first task at cost 0.
• Complete the third task at cost 2.
• Complete the second task at cost 3.

Sample Input 2

11 5 5

Sample Output 2

6

Sample Input 3

100 100 100

Sample Output 3

0

见题面 Input 部分

见题面 Output 部分