Problem Description
You are given an integer array nums and an integer k. An integer x is almost missing from nums if x appears in exactly one subarray of size k within nums. Return the largest almost missing integer from nums. If no such integer exists, return -1.
Key Insights
- A subarray is a contiguous sequence of elements.
- We need to count the occurrences of each integer in all possible subarrays of size k.
- An integer is considered "almost missing" if it appears exactly once in the counted subarrays.
- To find the largest "almost missing" integer, we will keep track of the maximum value that meets the criteria.
Space and Time Complexity
Time Complexity: O(n * k), where n is the length of nums. We need to traverse through all possible subarrays of size k. Space Complexity: O(1), as we only use a fixed amount of additional space regardless of the input size.
Solution
We will iterate through all possible subarrays of size k in the array nums and count the occurrences of each integer using a hash map (or dictionary). After counting, we will check for integers that appear exactly once and keep track of the largest integer that satisfies this condition.