import java.util.Scanner;
public class Main {
public static int maxGap(int[] nums) {
if (nums == null || nums.length < 2) {
return 0;
}
int len = nums.length;
int min = Integer.MAX_VALUE;
int max = Integer.MIN_VALUE;
for (int i = 0; i < len; i++) {
min = Math.min(min, nums[i]);
max = Math.max(max, nums[i]);
}
if (min == max) {
return 0;
}
boolean[] hasNum = new boolean[len + 1]; //判断该序号桶中是否存在数据
int[] maxs = new int[len + 1]; //记录每一个桶里面的最大值与最小值
int[] mins = new int[len + 1];
int bid = 0;
for (int i = 0; i < len; i++) {
bid = bucket(nums[i], len, min, max); //计算桶号
maxs[bid] = hasNum[bid] ? Math.max(maxs[bid], nums[i]) : nums[i];
mins[bid] = hasNum[bid] ? Math.min(mins[bid], nums[i]) : nums[i];
hasNum[bid] = true;
}
int res = 0;
int lastMax = maxs[0]; //前一个非空桶中的最大值[桶的序号0-N]
int i = 1;
for (; i <= len; i++) {
if (hasNum[i]) {
res = Math.max(res, mins[i] - lastMax);
lastMax = maxs[i];
}
}
return res;
}
//计算数据应该放的桶的位置
public static int bucket(long num, long len, long min, long max) {
//每一个桶的范围(max-min)/len
return (int) ((num - min) * len / (max - min));
}
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
int n=in.nextInt();
int[] nums=new int[n];
for (int i = 0; i <n ; i++) {
nums[i]=in.nextInt();
}
int res=maxGap(nums);
System.out.println(res);
}
}