Minimum Time to Make Array Sum At Most x
A hard-tier problem at 25% community acceptance, tagged with Array, Dynamic Programming, Sorting. Reported in interviews at Jane Street and 0 others.
Jane Street asks this problem, and at 25% acceptance, it's not a warm-up. You're looking at an array where you need to reduce the sum to at most x. The catch: each operation costs time, and you want the minimum time possible. This is dynamic programming wrapped in a greedy insight. Most candidates see the array and think brute force, then run into exponential blowup. The actual pattern relies on sorting, DP state transitions, and understanding that not all operations are equally valuable. If you hit this live and the greedy angle doesn't click, StealthCoder surfaces the working DP recurrence in seconds.
Companies that ask "Minimum Time to Make Array Sum At Most x"
Minimum Time to Make Array Sum At Most x 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 because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround.
Get StealthCoderThe core trick is realizing you should prioritize reducing the largest elements first, then model the problem as a DP where state tracks time spent and sum achieved. Sorting the array in descending order is step one. From there, the DP builds up: for each operation cost t, what's the maximum sum reduction you can achieve. The pitfall most hit: treating operations as interchangeable, or missing that you can apply multiple operations to the same element. The problem also has a hidden constraint check at the end, where you verify the resulting sum against x. Common failures come from incomplete exploration of the operation space or miscounting the time cost of a sequence. If you're prepping, trace through small examples by hand first to lock in the state definition before coding the table.
Pattern tags
You know the problem.
Make sure you actually pass it.
Minimum Time to Make Array Sum At Most x recycles across companies for a reason. It's hard-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 because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Minimum Time to Make Array Sum At Most x interview FAQ
Is this really a Jane Street problem or just a LeetCode hard?+
Jane Street has reported asking it. The 25% acceptance rate reflects its actual difficulty in live interviews, not inflated LeetCode difficulty ratings. Expect it if you interview there. If you don't, knowing the pattern is still a strong DP signal.
What's the main thing I'm missing if I get stuck?+
Most candidates miss that you need to pick which elements to reduce and in what order to minimize total time. The DP isn't about finding one optimal path; it's about exploring all valid sequences of operations and extracting the cheapest one that hits the target.
Does sorting really help here?+
Yes. Sorting descending ensures you consider high-value reductions first in your DP state. Without it, your DP space balloons and you lose the greedy property that makes the solution tractable in polynomial time.
How does this relate to Array and Sorting as topics?+
Array is the input structure; Sorting is the preprocessing step that makes DP feasible. Dynamic Programming is where the real work happens. All three topics are load-bearing in the solution.
Can I code this in a live assessment without panic?+
Only if you've traced the DP table by hand first. The state definition and transition are non-obvious. In the real assessment, if the pattern doesn't surface in 10 to 15 minutes, you're better off pulling a hint or letting StealthCoder show you the recurrence than grinding blind.
Want the actual problem statement? View "Minimum Time to Make Array Sum At Most x" on LeetCode →