const INF:i32 = std::i32::MAX;
fn getline() -> String {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();
	return s;
}
fn main() {
	let n:i32 = getline().trim().parse().unwrap();
    let mut m = 0;
    if n != 1 {
        let mut xs:Vec<i32> = getline().trim().split(' ').map(|x| x.parse().unwrap()).collect();
        xs.sort();
        m = INF;
        let mut p = xs[0];
        for i in 1 .. xs.len() {
            let x = xs[i];
            let d = x - p;
            if d != 0 && d < m {
                m = d;
            }
            p = x;
        }
        if m == INF {
            m = 0;
        }
    }
    println!("{}", m);
}