import java.util.Scanner;

class No_135 {
	public static void main(String args[]) {

		Scanner stdIn = new Scanner(System.in);		

		int num = stdIn.nextInt();

		int vc[] = new int[num];

		for (int i = 0; i < num; i++) {
			vc[i] = stdIn.nextInt();
		}
		int min = 0;
		int tmp;
		for (int i = 0; i < num; i++) {
			for (int k = 0; k < num; k++) {
				if (vc[i] == vc[k]) { continue; }
				if ( min == 0 ) {
					min = Math.abs(vc[i] - vc[k]);
				}
				tmp = Math.abs(vc[i] - vc[k]);
				if ( tmp < min ) {
					min = tmp;
				}
			}
		}
		System.out.println(min);
	}
}