Merge two sorted arrays `nums1` and `nums2` into one sorted array. Variant **#9**.
Example 1
Input: nums1 = [9,11,13,15,17,19,21], nums2 = [10,12,14,16]
Output: [9,10,11,12,13,14,15,16,17,19,21]
Constraints
Acceptance: 71% · Topics: array, sorting, two-pointers