Hudson River Trading coding interview
questions, leaked.
9 problems reported across recent Hudson River Trading interviews. Top patterns: array, math, graph. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
Hudson River Trading's assessment is 4 easy, 2 medium, 3 hard, and they're heavy on arrays and math. You'll see pattern detection, integer manipulation, graph problems. The difficulty cliff is real: most candidates will nail the easy batch, then hit arrays combined with DP or hard graph work and stall. If you blank on a grid DP or graph traversal problem mid-assessment, StealthCoder runs invisibly and surfaces a solution in seconds. This is the hedge for whatever you didn't drill in time.
Top problems at Hudson River Trading
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Detect Pattern of Length M Repeated K or More Times | EASY | 100.0 | 43% | Array · Enumeration |
| 02 | Convert Integer to the Sum of Two No-Zero Integers | EASY | 97.8 | 54% | Math |
| 03 | Number of Steps to Reduce a Number to Zero | EASY | 97.8 | 86% | Math · Bit Manipulation |
| 04 | Add Edges to Make Degrees of All Nodes Even | HARD | 97.8 | 34% | Hash Table · Graph |
| 05 | Maximum 69 Number | EASY | 97.8 | 82% | Math · Greedy |
| 06 | Maximum Total Importance of Roads | MEDIUM | 97.8 | 69% | Greedy · Graph · Sorting |
| 07 | Maximum Score From Grid Operations | HARD | 97.8 | 24% | Array · Dynamic Programming · Matrix |
| 08 | Longest Path With Different Adjacent Characters | HARD | 97.8 | 54% | Array · String · Tree |
| 09 | Remove Comments | MEDIUM | 60.9 | 39% | Array · String |
Frequencies derived from public community-tagged interview reports. Click a row to view on LeetCode.
You have a week, maybe less. You can't out-grind the list above. StealthCoder runs invisibly during the actual Hudson River Trading OA. The proctor cannot see it. Screen share cannot detect it. Built because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround.
Get StealthCoder- array4 · 44%
- math3 · 33%
- graph3 · 33%
- greedy2 · 22%
- string2 · 22%
- enumeration1 · 11%
- bit manipulation1 · 11%
- hash table1 · 11%
- sorting1 · 11%
- heap priority queue1 · 11%
Arrays dominate the problem set (4 occurrences), followed by math and graph (3 each). Early wins come from the easy math and array enumeration problems, but the real weight is in hard problems that layer arrays with DP, or graphs with hashing and sorting. Greedy and graph appear paired on the medium-hard tier. String and bit manipulation are present but lower frequency. Drill arrays and math fundamentals first, because they're your confidence builders and appear earliest in most candidate runs. Graph and DP come next. If you're weak on hard array-DP hybrids or topological sort by interview day, StealthCoder is your safety net on live assessment.
Companies with similar patterns
If you prepped for Hudson River Trading, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Hudson River Trading.
Memorizing every problem above in a week is a fantasy. StealthCoder is the hedge: an AI overlay that's invisible during screen share. It reads the problem on screen 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.
Hudson River Trading interview FAQ
Should I focus more on arrays or graphs for Hudson River Trading?+
Arrays hit 4 problems, graph hits 3. Start with arrays and math to build speed on easy rounds. Graph matters on hard problems, especially when mixed with hashing or topological sort. You need both, but array fluency pays off first.
How many math problems should I solve before the assessment?+
Math appears in 3 of 9 problems, all easy. These are your gimmes. Spend a day on integer manipulation and greedy math problems. Don't over-prep math; the real filter is arrays and DP on harder problems.
What's the hardest topic combination I'll face?+
Arrays with DP and matrix operations, plus graph problems involving topological sort and DFS. These are your 3 hard problems. If you haven't solved a DP grid problem or topological sort recently, drill those two patterns hard.
Is bit manipulation critical for Hudson River Trading?+
Bit manipulation appears once, paired with math on an easy problem. It's not a focus. Master arrays, graph, and DP first. Bit tricks are a nice-to-have, not a make-or-break skill here.
How much time should I spend on greedy vs dynamic programming?+
Greedy appears in 2 problems, often mixed with graph or math. DP is bundled with the hardest array problem. Both matter, but DP carries more weight on the hard tier. Spend 60 percent of advanced prep on DP, 40 on greedy patterns.