Reverse Bits
A easy-tier problem at 63% community acceptance, tagged with Divide and Conquer, Bit Manipulation. Reported in interviews at Nvidia and 3 others.
Reverse Bits lands on assessments at Nvidia, Qualcomm, Airbnb, and Google. It looks trivial on the surface: flip the bit order of a 32-bit unsigned integer. The catch is that naive solutions often fail on edge cases or time out on large inputs. The acceptance rate sits at 63%, which means candidates who haven't drilled bit manipulation patterns tend to stumble. If you hit this problem live and panic, StealthCoder surfaces the optimal approach invisibly during your assessment, so you never have to guess whether you're reversing correctly.
Companies that ask "Reverse Bits"
Reverse Bits 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. Built by an Amazon engineer who used it to pass JPMorgan's OA and system design loop.
Get StealthCoderThe problem forces you to think about bit manipulation at a low level. Most candidates try iterating through bits and rebuilding the result with shifts, which works but feels clunky. The real pattern is recognizing that you're extracting each bit from the original number and placing it in the reversed position. The trick: use a mask to pull one bit at a time, shift it into place, and move to the next. Some people miss the order of operations or mess up the shift amounts. A divide-and-conquer approach also works if you swap adjacent bit groups, pairs, then individual bits. When you're under time pressure in the live OA and bit logic isn't your strong suit, StealthCoder's instant working solution cuts through the confusion and lets you move on to harder problems.
Pattern tags
You know the problem.
Make sure you actually pass it.
Reverse Bits recycles across companies for a reason. It's easy-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. Built by an Amazon engineer who used it to pass JPMorgan's OA and system design loop. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Reverse Bits interview FAQ
Is Reverse Bits actually asked at Google and other major companies?+
Yes. Google, Nvidia, Qualcomm, and Airbnb have all asked it. It's not the hardest problem, but it's a classic way to screen for bit manipulation comfort. If you're interviewing there, you should be able to solve it clean in under 5 minutes.
What's the trap most people fall into?+
Forgetting to handle the full 32-bit range or messing up the shift direction. Some people reverse the bits but then mask incorrectly, leaving garbage bits in the output. The shift order and final masking are where the mistakes hide.
Do I need to know divide-and-conquer for this, or is iteration enough?+
Iteration is simpler and totally fine. Divide-and-conquer (swapping bit blocks recursively) is elegant but overkill for a 32-bit number. Master the iterative bit-extraction method first. The topics list includes both because the problem can be solved either way.
How does this relate to broader bit manipulation topics?+
Reverse Bits teaches you bit extraction and placement, skills you'll need for problems like Single Number, Majority Element, and Power of Two. It's foundational. If bit shifts and masks feel fuzzy, this is where you build that muscle.
What if I blank on the bit logic during the real assessment?+
That's exactly what StealthCoder handles. It reads your problem, surfaces a working solution in seconds, and runs invisibly on screen share. You paste the code, explain it confidently, and move forward. The safety net is there if the pattern doesn't click under pressure.
Want the actual problem statement? View "Reverse Bits" on LeetCode →