D - Empty Intersection

You are given two arrays $a$ and $b$, consisting of $n$ and $m$ integers respectively. You can perform the following operation any number of times (possibly zero): - Select an element $e$ ($e \ge 2$) from either $a$ or $b$. - Remove exactly one occurrence of $e$ from the array from which it was taken. - Choose two integers $x$ and $y$ such that $\min(x, y) \ge 1$ and $x + y = e$. - Insert $x$ and