Description

Given $n$ integers (numbers may repeat), choose any subset of them so that their XOR sum is maximized.

Input Format

The first line contains an integer $n$, the number of elements. The next line contains $n$ integers.

Output Format

Output a single integer on one line, the answer.

2
1 1

1

4
1 5 9 4

13

Hint

Constraints: $1 \leq n \leq 50$, $0 \leq S_i < 2^{50}$.

Translated by ChatGPT 5