public class No_166 {

	public static void main(String[] args) {
		java.util.Scanner sc = new java.util.Scanner(System.in);
		int n = sc.nextInt();
		int[] X = new int[n];
		int distance = Integer.MAX_VALUE;

		for (int i = 0; i < n; i++) {
			X[i] = sc.nextInt();
		}

		java.util.Arrays.sort(X);

		for (int i = 0; i < X.length - 1; i++) {
			if (X[i] == X[i + 1]) {
				continue;
			}
			distance = Math.min(distance, Math.abs(X[i] - X[i + 1]));
		}

		if (distance != Integer.MAX_VALUE) {
			System.out.println(distance);
		} else {
			System.out.println(0);
		}
		sc.close();

	}

}