import sys
from itertools import islice, product


def _solve(N, K, values):
    return max(values) - min(values)


def solve(in_):
    N = int(next(in_))
    K = int(next(in_))
    values = [int(line) for line in islice(in_, N)]
    return _solve(N, K, values)
    

def main():
    answer = solve(sys.stdin.buffer)
    print(answer)


if __name__ == '__main__':
    main()