Problem:
Score : 200 points

Problem Statement

It is only six months until Christmas, and AtCoDeer the reindeer is now planning his travel to deliver gifts.

There are N houses along TopCoDeer street. The i-th house is located at coordinate a_i. He has decided to deliver gifts to all these houses.

Find the minimum distance to be traveled when AtCoDeer can start and end his travel at any positions.

Constraints

1 ≤ N ≤ 100

0 ≤ a_i ≤ 1000

a_i is an integer.

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the minimum distance to be traveled.

Sample Input 1

4
2 3 7 9

Sample Output 1

7

The travel distance of 7 can be achieved by starting at coordinate 9 and traveling straight to coordinate 2.

It is not possible to do with a travel distance of less than 7, and thus 7 is the minimum distance to be traveled.

Sample Input 2

8
3 1 4 1 5 9 2 6

Sample Output 2

8

There may be more than one house at a position.

Solution in OCaml (4.02.3) (judge verdict: Accepted)

let () =
  let n = read_int () in 
  let a = Array.init n (fun _ -> Scanf.scanf "%d " (fun x -> x)) in 
  let () = Array.fast_sort compare a in 
  let rec f i sum =
    if i = n then sum else f (i + 1) (sum + a.(i) - a.(i - 1))
  in f 1 0
     |> Printf.printf "%d\n"