Problem - Create Maximum Number

Given two arrays of digits and an integer $k$, create the maximum number of length $k$ from digits of both arrays. The relative order within each array must be preserved. For $nums1 = [3,4,6,5]$, $nums2 = [9,1,2,5,8,3]$, $k = 5$, the answer is $[9,8,6,5,3]$. It combines "max number from one array" with "merge two arrays maximally." Break it into subproblems. Constraint: you must preserve relative order within each array.

If $nums1 = [6,7]$ and you pick $6$, you cannot later pick $7$ without $6$. The split must satisfy $i + j = k$ and $i \leq len(nums1)$, $j \leq len(nums2)$.