How should I practice Merge Sorted Array?

Start by reading the full statement, solve the visible examples, then compare the pattern against related DP World onsite interview problems in FastPrep.

Is Merge Sorted Array associated with DP World?

FastPrep tags this as a DP World onsite interview coding practice problem when the problem catalog has that company and stage context.

Merge Sorted Array

DP World● EasyFULLTIMEONSITE INTERVIEW

Problem statement

You are given two integer arrays, nums1 and nums2, and two integers, m and n.

The first m values of nums1 are its real values. Its last n slots hold 0 and are empty space. nums2 holds exactly n values. The real values of nums1 and all values of nums2 are sorted in non-decreasing order.

Merge nums2 into nums1 so that nums1 holds all m + n values in non-decreasing order, then return nums1.

Follow-up

Now suppose neither array has empty space: one array holds m values and the other holds n values. Without using another array, how would you rearrange the values so that the first array holds the m smallest values and the second holds the rest, both sorted? Your function only solves the version above. The editorial covers this follow-up.

Function

merge(nums1: int[], m: int, nums2: int[], n: int) → int[]

Examples

Example 1

nums1 = [1,2,3,0,0,0]m = 3nums2 = [2,5,6]n = 3return = [1,2,2,3,5,6]

The real values are [1,2,3] in nums1 and [2,5,6] in nums2. Merged in order, they give [1,2,2,3,5,6], which fills all six slots of nums1.

Example 2

nums1 = [1]m = 1nums2 = []n = 0return = [1]

nums2 is empty, so nums1 stays [1].

Example 3

nums1 = [0]m = 0nums2 = [1]n = 1return = [1]

m is 0, so nums1 has no real values. Its only slot is empty space, and the result is [1].

Constraints

nums1.length == m + n
nums2.length == n
0 <= m, n <= 200
1 <= m + n <= 200
-10^9 <= nums1[i], nums2[j] <= 10^9
The first m values of nums1 and all values of nums2 are sorted in non-decreasing order.
The last n values of nums1 are 0.