import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int[] x = new int[N];
    for(int i = 0; i < N; i++) {
      x[i] = sc.nextInt();
    }
    Arrays.sort(x);
    int ans = Integer.MAX_VALUE;
    for(int i = 1; i < N; i++) {
      if(x[i] > x[i - 1]) ans = Math.min(ans, x[i] - x[i - 1]);
    }
    if(ans == Integer.MAX_VALUE) ans = 0;
    System.out.println(ans);
  }
}