Maximum Subarray

Given two arrays $A$ and $B$ of sizes $N$ and $M$ respectively. You can apply the following operation until the array $B$ is non-empty: - Choose either the **first** or the **last** element of array $B$. - Insert the chosen element to either the **front** or the **back** of array $A$. - Delete the chosen element from array $B$. For example, let $A = [9, 7]$ and $B = [1, 3, 2]$. In one operation,