use std::io;

fn read() -> i32 {
	let mut line = String::new();
	io::stdin().read_line(&mut line).unwrap();
	line.trim().parse().unwrap()
}

fn main() {
	let N = read();
	let K = read();
	let mut n = vec![0; N as usize];
	for i in 0..N {
		n[i as usize] = read();
	}
	n.sort();
	println!("{}", n[n.len() - 1] -n[0]);
}