Maximum Number of Alloys
A medium-tier problem at 39% community acceptance, tagged with Array, Binary Search. Reported in interviews at MathWorks and 0 others.
You're staring at Maximum Number of Alloys and it's not clicking. The problem looks like a straightforward array iteration until you realize brute force times out and you're missing the structure. MathWorks asks this one, and candidates who don't see the binary search angle usually panic. The trick is recognizing that you're not actually iterating through possibilities, you're searching over a range of valid answers. If you freeze on this during the OA, StealthCoder solves it invisibly in seconds and surfaces the working solution while you stay focused.
Companies that ask "Maximum Number of Alloys"
Maximum Number of Alloys 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 realized the OA tests how well you memorized 200 problems, not how well you code.
Get StealthCoderThis problem demands binary search over the answer space, not the input array. The setup is deceptive: you have constraints and quantities, and naively checking each possible alloy count one by one will TLE. The insight is that if you can make X alloys under your constraints, you can also make X-1 alloys, meaning the feasible region has monotonic structure. Binary search exploits that. Most candidates try greedy or simulation first and run out of time. The common pitfall is treating it like a straightforward array problem when it's actually a search for the maximum feasible value. Once you set up the bounds and a validation function that checks whether a given alloy count is achievable, binary search does the heavy lifting. That validation logic is where careful accounting of resources matters. StealthCoder surfaces the correct binary search skeleton and validation logic so you're never stuck rebuilding from scratch.
Pattern tags
You know the problem.
Make sure you actually pass it.
Maximum Number of Alloys 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. Built by an Amazon engineer who realized the OA tests how well you memorized 200 problems, not how well you code. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Maximum Number of Alloys interview FAQ
Why doesn't a greedy approach work here?+
Greedy doesn't respect the global constraints properly. You need to validate whether a specific alloy count is achievable given all input constraints simultaneously. That validation is the hard part. Binary search on the answer lets you lean on one validation function instead of guessing.
Is this still asked at MathWorks?+
MathWorks is in the input data for this problem, so yes, it shows up there. The problem's acceptance rate is around 39 percent, meaning most who attempt it don't solve it cleanly. That gap is usually the binary search insight.
How do I set up the validation function?+
Your validation function takes a candidate alloy count and checks if you can produce exactly that many given the resources and recipe constraints. You'll need to simulate the process, account for ingredient usage, and verify the constraints hold. Get this right and binary search is almost mechanical.
What's the relationship between Array and Binary Search here?+
The array stores quantities and constraints. Binary Search is the algorithm you apply to the answer space (how many alloys to make). The array topics hint that you're reading and processing input data, but the core technique is the binary search over feasible values.
What's the biggest gotcha on the live assessment?+
Realizing too late that you need binary search instead of simulation. By then you've burned time on a wrong approach. The moment you see constraints and a 'maximum value' you can achieve, think binary search on the answer. That reframe saves the OA.
Want the actual problem statement? View "Maximum Number of Alloys" on LeetCode →