use proconio::input;

fn main() {
	input! {
		n: usize,
		x: [isize; n],
	}

	let mut arr = x.clone();
	arr.sort();
	arr.dedup();

    let ans: isize = arr.windows(2)
        .map(|arr| arr[1] - arr[0])
        .min()
        .unwrap_or(0);

	println!("{ans}");
}