package yukicoder;

import java.util.Arrays;
import java.util.Scanner;

import org.omg.PortableInterceptor.Interceptor;

public class Yuki135 {

	public static void main(String[] args) {

		Scanner scan = new Scanner(System.in);
		int n = scan.nextInt();
		int x[] = new int[n];

		for (int i = 0; i < n; i++) {
			x[i] = scan.nextInt();
		}
		scan.close();
		Arrays.sort(x);
		
		int ans = 0;
		int ans2 = 0;
		for (int i = 0; i < n-1; i++) {
			if(x[i] != 0){
				if (x[i + 1] > x[i]) {
					ans = x[i + 1] - x[i];
				} else if(x[i + 1] < x[i]){
					ans = x[i] - x[i + 1];
				} else if(x[i + 1] == x[i]){
					ans = x[i];
				}
				if(ans2 == 0){
					ans2 = ans;
				}else if(ans2 > ans && ans != 0){
					ans2 = ans;
				}
			}
		}
		System.out.println(ans2);

		/*
		 * int ans = 0; int perseAns = 0; for(int i = 0; i < n; i++) { for(int j
		 * = 0; j < n; j++) {
		 * 
		 * if( x[i] > x[j] ){ ans = x[i]-x[j]; } else { ans = x[j]-x[i]; }
		 * 
		 * if(perseAns == 0) { perseAns = ans; }else if ( ans < perseAns && ans
		 * != 0) { perseAns = ans; } } } System.out.println(perseAns);
		 */
	}
}