Codeforces Round #276 (Div. 1)B（暴力）_html/css_WEB-ITnose

B. Maximum Value

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

You are given a sequence a consisting of n integers. Find the maximum possible value of  (integer remainder of ai divided by aj), where 1?≤?i,?j?≤?n and ai?≥?aj.

Input

The first line contains integer n ? the length of the sequence (1?≤?n?≤?2·105).

The second line contains n space-separated integers ai (1?≤?ai?≤?106).

Output

Print the answer to the problem.

Sample test(s)

input

33 4 5

output

题意：RT

思路：可以用nearest[i]表示离i最近且比i小的数

            然后对于每个数x，暴力遍历x*2，x*3，.....,x*k，这时nearest数组派上用场了，直接由nearest[x*k]%x取最大值即可