use std::io::*;
use std::str::FromStr;
use std::cmp;

#[allow(dead_code)]
fn get_line() -> String {
    let stdin = stdin();
    let mut line = String::new();
    stdin.lock().read_line(&mut line).expect("io error.");
    line.trim().to_string()
}

#[allow(dead_code)]
fn get_word<T: FromStr>() -> T {
    (&get_line()).parse().ok().expect("parse error.")
}

#[allow(dead_code)]
fn get_vec<T: FromStr>() -> Vec<T> {
    (&get_line()).split(' ').map(|x| x.parse().ok().expect("parse error.")).collect()
}

fn main() {
    let _ = get_word::<usize>();
    let mut x = get_vec::<i64>();

    x.sort();
    x.dedup();
    let n = x.len();
    let mut ans: i64 = 10i64.pow(10);

    if n == 1 {ans = 0};
    for i in 0..n-1 {
        ans = cmp::min(ans, x[i + 1] - x[i]);
    }

    println!("{}", ans);
}