Problem:
Score : 200 points

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

2 \leq N \leq 100

1 \leq A_i \leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N

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 A_3-A_1=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

Solution in Common Lisp (SBCL 1.1.14) (judge verdict: Accepted)

(defparameter n (read))
(defparameter s (read-line))

(defun split-py (str)
  (let ((pos (position #\space str)))
    (cond ((null pos) (list str))
           (t (cons (subseq str 0 pos) (split-py (subseq str (1+ pos))))))))

; incf は1+してsetq
; 1+ は1+した値を返すだけ

(let ((L (sort (mapcar (lambda (x) (read-from-string x)) (split-py s)) #'<)))
  (princ (- (car (last L)) (first L))))