Maximum OR
A medium-tier problem at 41% community acceptance, tagged with Array, Greedy, Bit Manipulation. Reported in interviews at DE Shaw and 0 others.
Maximum OR is a medium-difficulty problem that shows up in DE Shaw's assessments and trips up candidates who don't spot the greedy pattern. You're given an array and need to partition or select elements to maximize a bitwise OR result. The acceptance rate sits at 41%, which tells you most people either brute-force it (too slow) or miss the insight that lets you build the answer incrementally. If this lands in your live OA and you blank on the strategy, StealthCoder surfaces the working solution in seconds, invisible to the proctor.
Companies that ask "Maximum OR"
Maximum OR 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 by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoderThe trick is recognizing that OR is monotonic: once a bit is set, it stays set. This means greedy works. Many candidates waste time trying dynamic programming or trying every subset, but the optimal approach tracks which bits you can activate and in what order to maximize the final result. Common pitfall: confusing this with a selection problem where you need to count how many elements to use versus a partitioning problem. The problem also tests whether you can think in terms of bit masks and prefix/suffix structures rather than just raw values. StealthCoder handles the greedy construction and bit logic so you don't get stuck on the implementation during a live screen share.
Pattern tags
You know the problem.
Make sure you actually pass it.
Maximum OR 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 by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Maximum OR interview FAQ
Is Maximum OR really asked at top companies like DE Shaw?+
Yes. DE Shaw's reports confirm this problem appears in their assessments. It's not a FAANG staple, but it shows up in specialized trading and systems firms that value bit manipulation and algorithmic insight. The 41% acceptance rate suggests it's a real filter.
What's the core trick I'm missing if I keep timing out?+
You're likely brute-forcing subsets. The insight is that OR is monotonic: bits never turn off. Use a greedy approach where you track which bits are reachable and build the maximum result by choosing elements that set new high bits first, not by trying every combination.
How does Greedy relate to Bit Manipulation here?+
Greedy lets you avoid exponential search. Bit Manipulation lets you reason about which bits matter. Together they mean: for each position or choice, pick the option that sets the highest unset bit. This transforms an exponential problem into linear or near-linear work.
Do I need Prefix Sum to solve this?+
Not always. Prefix Sum becomes useful if the problem adds constraints like 'you must take a contiguous subarray' or 'count elements in ranges.' Without those constraints, greedy bit selection alone often solves it. Check the problem statement carefully.
If I haven't seen this pattern before, can I still solve it live?+
It's hard. The greedy insight isn't obvious, and bit manipulation under time pressure is error-prone. That's where StealthCoder comes in. If you hit this on an OA and can't find the pattern, it runs invisibly and gives you a working solution to submit or adapt.
Want the actual problem statement? View "Maximum OR" on LeetCode →