Practice: Search in Rotated Sorted Array
Problem: https://leetcode.com/problems/search-in-rotated-sorted-array/
Recognition reminder: the array was sorted, then rotated at some unknown pivot, and you still need O(log n). The array is not globally sorted, but at any midpoint one of the two halves is. That local order is enough to binary search.
Before you start (the five-beat rhythm)
- Your Pattern Card for this week is already written.
- Name the pattern aloud and write your approach as a plain-English comment before any code.
- Struggle floor: 25 minutes unaided. No hints, no AI, no Discuss tab.
- If stuck past the floor, ask the tutor for a hint. Six rungs, one per ask.
- Debrief in your commit message before moving to the next problem.
Your target
Fill these in yourself before you look at anyone else’s solution:
Target time complexity: ____
Target space complexity: ____
The constraint that makes this interesting is O(log n); a linear scan passes the judge but fails the interview. The idea to find is that at any midpoint one half is still cleanly sorted, and inside a sorted half you can tell in one comparison whether the target lives there; work out for yourself how to identify the sorted half and how to decide which half to keep. Write down in your debrief why exactly one half is always sorted.
Where your code goes
Write your solution in your own work repo (see getting-started.md), not in this folder. This folder ships only the problem spec and a provided-example test (tests/test_provided.py) so you can check the given cases locally before you submit to LeetCode’s judge. The judge is the oracle; the tutor will not confirm your answer by reading it.
Debrief (paste into your commit message)
1. What pattern did this turn out to be?
2. What was the trigger phrase or input shape that should have made me reach for it?
3. What was the time and space complexity, and what would dominate at scale?
4. What edge case would have broken my first attempt?
5. What would I do differently in three days when I see this cold?