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 Haskell (GHC 7.10.3) (judge verdict: Wrong Answer)

main :: IO ()
main = do
  _  <- getLine
  as <- map read . words <$> getLine :: IO [Int]
  print . f $ as

f ::[Int] -> Int
f = g (1,1) 

g :: (Int,Int) -> [Int] -> Int
g (s,l) [] = l-s
g sl@(s,l) (x:xs)
  | x < s = g (x,l) xs
  | l < x = g (s,x) xs
  | otherwise = g sl xs