Find the elements that are missing from an array relative to a reference range or expected set.
You are given an array of integers and some expected value range or reference sequence. Return the elements from the expected set that do not appear in the array.
The task is usually solved by tracking which values have been seen, then reporting the values that were never encountered. Depending on the exact input format, the expected set may be a contiguous range such as 1..n or another clearly defined list of values.
Input Format
- An integer array
nums. - Additional information describing the expected values, such as a range length
nor a reference list.
Interpret the exact expected set from the problem input description.
Output Format
Return the missing value(s) in increasing order or in the required order specified by the statement.
Constraints
- The array may contain duplicates.
- Values are typically within a bounded integer range.
- Aim for an approach that is linear or near-linear in time.
Example 1
Input
nums = [1, 2, 4, 6], expected range = 1..6
Output
[3, 5]
Explanation
The numbers 3 and 5 never appear in the array, so they are returned as the missing elements.
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