And Or Union

You are given an array $A$ consisting of $N$ integers. From array $A$, we create a new array $B$ containing all pairwise bitwise ANDs of elements from $A$. That is, $B$ consists of $N\cdot(N-1)/2$ elements, each of the form $A_i \mathbin{\&} A_j$ for some $1 \leq i \lt j \leq N$. In array $B$, we repeat the following process till there is only one element remaining: - Let the current maximum and