Search in Rotated Sorted Array II
A medium-tier problem at 39% community acceptance, tagged with Array, Binary Search. Reported in interviews at Amazon and 7 others.
Search in Rotated Sorted Array II is a medium-difficulty problem that shows up in interviews at Amazon, Microsoft, Meta, and Uber. You probably nailed the version without duplicates. This one breaks your binary search logic the moment duplicates enter a rotation point. The acceptance rate sits at 39 percent, which means most people either solve it cleanly or tank it. The trick isn't obvious until you've seen the edge case that collapses standard binary search into linear time. If this problem hits your live assessment and you blank on the duplicate-handling pattern, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "Search in Rotated Sorted Array II"
Search in Rotated Sorted Array II is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Made for the engineer who has done the work but might still blank with a webcam pointed at him.
Get StealthCoderThe core problem: binary search on a rotated sorted array falls apart when duplicates live at the rotation boundary. You can't tell which half is sorted just by comparing endpoints. The solution shrinks the search space by skipping duplicates at the left and right borders until you can trust the comparison again. This turns worst-case into O(n) on pathological inputs like [1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1], but still O(log n) on typical data. Most candidates either ignore duplicates and submit broken code, or immediately pivot to linear search and miss the binary search win. Array and Binary Search are the named topics, and the skill being tested is recognizing when your standard algorithm needs a surgical fix, not a rewrite. If you hit this live and haven't drilled the duplicate-skipping pattern, StealthCoder hedges the gap.
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Search in Rotated Sorted Array II recycles across companies for a reason. It's medium-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Made for the engineer who has done the work but might still blank with a webcam pointed at him. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Search in Rotated Sorted Array II interview FAQ
How is this different from the standard rotated array problem?+
Duplicates destroy the binary search invariant. In the no-duplicate version, you always know which half is sorted by comparing ends. With duplicates, [1,3,1,1,1] and [1,1,1,3,1] both have left and right as 1, so you can't decide. You must shrink the search space by skipping duplicates at boundaries first.
Why is the acceptance rate so low?+
Most candidates either submit a binary search that fails on duplicates, or give up and go linear. The duplicate-skipping fix is small but non-obvious. You have to think through the edge case where you can't determine which half is sorted, then write the boundary-skip logic cleanly.
Is this still asked at FAANG?+
Yes. Amazon, Microsoft, Meta, Uber, and Bloomberg all report asking it. It's a real gating problem on medium-difficulty OAs. The companies hiring for this want to see both binary search competence and the humility to abandon it when data breaks your assumptions.
What's the trick to getting this right in an interview?+
Recognize that duplicates at left and right pointers block your half-detection. Write the while loop that shrinks left and right until they're no longer equal to mid, then proceed with standard binary search. Test explicitly on cases like [1,3,1,1,1] and [1,1,1,3,1] before you submit.
How does this relate to the Array and Binary Search topics?+
It tests both. You need to understand arrays and index manipulation, but the core challenge is binary search adaptation. It's the problem that separates people who memorized binary search from people who understand when and how to modify it.
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