You are given a array of integers. Find the diff between the maximum average value and minimum average value of sub-sequences of array.

Input:
First line contains a single integer denoting N, the number of elements of array.
Next line contains N space separated integers denoting the array.

Output:

Print the greatest integer of the answer.
Greatest integer of 2.5 is 2.
Greatest integer of 2 is 2.

Constraints

1 ≤ N ≤ 500,
0 ≤ A[i] ≤ 10^5

SAMPLE INPUT
4
1 2 1 2

SAMPLE OUTPUT
1

Explanation

Minimum Average value of sub-sequence 1, 1 is 1. Maximum Average value of sub-sequence 2, 2 is 2.Therefore answer is 2-1=1

P.S. : A subsequence of a string is not necessarily continuous.

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