module main;

import std;

void main()
{
	// 入力
	int N = readln.chomp.to!int;
	auto X = readln.split.to!(int[]);
	// 答えの計算と出力
	if (X.all!(a => a == X[0])) {
		writeln(0);
		return;
	}
	int ans = 10 ^^ 9;
	foreach (i; 0 .. N - 1) {
		foreach (j; i + 1 .. N) {
			if (X[i] == X[j]) continue;
			ans = min(ans, abs(X[i] - X[j]));
		}
	}
	writeln(ans);
}