fn main() {
    let n: u32 = read();
    let _k: u32 = read();

    let mut max: i32 = std::i32::MIN;
    let mut min: i32 = std::i32::MAX;

    for _i in 0..n {
        let temp: i32 = read();

        //最大最小の更新
        if max < temp {
            max = temp;
        }
        if min > temp {
            min = temp;
        }
    }

    println!("{}", max - min);

}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().split_whitespace()
        .map(|e| e.parse().ok().unwrap()).collect()
}