num = int(input())
data = input().split(' ')
int_data = [int(s) for s in data]
list.sort(int_data, reverse = True)
ans = [int_data[i] - int_data[i + 1] for i in range(num - 1) if int_data[i] - int_data[i + 1] != 0]
list.sort(ans)
print(ans[0])