maxdifference

Problem Statement

You are given an integer sequence A of length N. Find the maximum absolute difference of two elements (with different indices) in A.

Constraints

Input

Input is given from Standard Input in the following format:

N
A1 A2 ... AN

Output

Print the maximum absolute difference of two elements (with different indices) in A.

Sample Input 1

4
1 4 6 3

Sample Output 1

5

The maximum absolute difference of two elements is A3-A1=6-1=5.

Sample Input 2

2
1000000000 1

Sample Output 2

999999999

Sample Input 3

5
1 1 1 1 1

Sample Output 3

0