Given an array of $n$ integers, your task is to find the maximum xor sum of a subset.

Input

The first line has an integer $n$: the size of the array.

The next line has $n$ integers $x_1,x_2,\dots,x_n$: the contents of the array.

Output

Print one integer: the maximum xor sum of a subset.

Constraints

• $1 \le n \le 2 \cdot 10^5$
• $0 \le x_i \le 10^9$

Example

Input:

4
1 6 12 6

Output:

13