What is the optimal time complexity of solving Search in Almost Sorted Array?

The optimized solution achieves a time complexity of O(n log n) by using sorting, mathematical shortcuts, or hash table lookups.

What is the auxiliary space complexity for Search in Almost Sorted Array?

The space complexity is O(1) since we only use a minimal/constant amount of extra memory for tracking variables (or auxiliary space if dynamic structures are allocated).

What are the typical edge cases we must handle in Search in Almost Sorted Array?

Key edge cases include empty collections, negative or large bounds causing integer overflow, arrays with only one element, or inputs where target criteria are not met.

How can we optimize the brute force approach for Search in Almost Sorted Array?

Brute force methods often inspect all possible combinations. We optimize this by sorting the input list to enable binary search, or tracking processed items in a set to avoid redundant nested loop lookups.

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Search in Almost Sorted Array

Learn how to solve the 'Search in Almost Sorted Array' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Write a function search_almost_sorted(arr, target) that searches for a target value in an almost sorted array arr. An almost sorted array is one in which an element that should be at index i in a fully sorted array can instead be at index i-1, i, or i+1. Return the 0-based index of the target if found, otherwise return -1.

Constraints

•1 <= len(arr) <= 10^5
•-10^9 <= arr[i], target <= 10^9
•All elements in arr are unique.

Examples

Example 1

Input

search_almost_sorted([10, 3, 40, 20, 50, 80, 70], 40)

Output

Explanation

40 is at index 2 (which is its correct position in a fully sorted version).

Example 2

Input

search_almost_sorted([10, 3, 40, 20, 50, 80, 70], 90)

Output

-1

Explanation

90 does not exist in the array.

Need a Hint?

Analyze the input constraints. Try sorting first (O(n log n)) or using a hash map/set to track seen elements in O(n) time.

Edge Cases to Watch

Empty list or null input variables
Single item lists/arrays
Extremely large input bounds causing integer or stack overflow

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