Given a list of integers, return the difference between the largest and smallest number in the list.

NOTE: To read the input list in Python, you can, for example, use the command lis=eval(input()) which stores the input list in the variable lis. To write the integer to the output you can, for example, use the print command followed by the name of the variable containing the calculated value.

Input

The first line contains a list of integers. The list always contains at least two numbers.

Output

The difference between the maximum and minimum number in the list.

Example

Input:
[54,33, 23, 12 ,2 ,6, 91]

Output:
89