OR XOR

You are given the following:

Two integers $N$ and $K$

An array $A$ of size $N$

Let sequence $B(B_1,B_2,$dots,$B_{2K})$ of size $2K$ is a subsequence of array A$.$Let's define

$F(B)=(B_1|B_2|dots|B_K)o+(B_{K+1}|B_{K+2}|dots|B_{2K}).$

Where denotes bitwise or operation and $o+$ denotes bitwise XOR operation.

Task

Determine the maximum value of $F(B)$ for all possible sequences $B.$

Note: A sequence $x$ is a subsequence of sequence $Y$ if $x$ cail be obtained from $Y$ by

deleting several $($possibly$,$ zero or all$)$ elements without changing the order of the

remaining elements.

Example

Assumptions

$N=3$

$k=1$

$A=[2,4,5]$

ApproachThere are $3$ subsequences of length $2$ which are as follows:

$B=[2,4],F(B)=2o+4=6$

$B=[2,5],F(B)=2o+5=7$

$B=[4,5],F(B)=4o+5=1$

write the code in C$++$