You are given an array consisting of n integers $a_1,a_2,..a_n$. Find the maximum value of xor of sum of 2 disjoint subarrays i.e maximize ( sum($l_1,r_1$) xor sum($l_2,r_2$) )
where $1\le l_1\le r_1$ < $l_2\le r_2\le n$.
Note: sum(l,r) denotes sum of elements from indices l to r both inclusive.

Input Format
First line contains number n denoting the number of array elements.
Second line contains n integers denoting $a_1,a_2,..a_n$.

Output Format
Output the required value.

Constraints
$1\le n\le 900$
$1\le a_i\le 100$