BNY Mellon coding interview
questions, leaked.
21 problems reported across recent BNY Mellon interviews. Top patterns: array, hash table, string. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
BNY Mellon's coding assessments lean heavily on array problems. Of the 21 problems in reported question sets, 14 involve arrays, and the spread across difficulty is skewed: 12 medium, 6 easy, 3 hard. Hash tables and strings appear frequently too. Most candidates spend prep time drilling Two Sum variants and greedy patterns, which is smart, but the real weight is array manipulation. If you can reason through an array problem under pressure, you'll clear most of the assessment. StealthCoder sits invisible during your live OA as a safety net for the moment you blank on a pattern you didn't drill.
Top problems at BNY Mellon
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Count Visited Nodes in a Directed Graph | HARD | 100.0 | 29% | Dynamic Programming · Graph · Memoization |
| 02 | Minimize Length of Array Using Operations | MEDIUM | 97.7 | 35% | Array · Math · Greedy |
| 03 | Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts | MEDIUM | 97.7 | 41% | Array · Greedy · Sorting |
| 04 | Sum of Distances | MEDIUM | 97.7 | 31% | Array · Hash Table · Prefix Sum |
| 05 | Group Anagrams | MEDIUM | 75.5 | 71% | Array · Hash Table · String |
| 06 | Minimum Number of Taps to Open to Water a Garden | HARD | 75.5 | 51% | Array · Dynamic Programming · Greedy |
| 07 | Minimum Number of Groups to Create a Valid Assignment | MEDIUM | 68.6 | 24% | Array · Hash Table · Greedy |
| 08 | Gas Station | MEDIUM | 68.6 | 46% | Array · Greedy |
| 09 | Palindromic Substrings | MEDIUM | 68.6 | 72% | Two Pointers · String · Dynamic Programming |
| 10 | Car Fleet | MEDIUM | 58.8 | 53% | Array · Stack · Sorting |
| 11 | Two Sum | EASY | 58.8 | 56% | Array · Hash Table |
| 12 | 3Sum | MEDIUM | 58.8 | 37% | Array · Two Pointers · Sorting |
| 13 | Find the Count of Monotonic Pairs II | HARD | 58.8 | 23% | Array · Math · Dynamic Programming |
| 14 | Count Vowel Substrings of a String | EASY | 58.8 | 71% | Hash Table · String |
| 15 | Total Cost to Hire K Workers | MEDIUM | 58.8 | 43% | Array · Two Pointers · Heap (Priority Queue) |
| 16 | Move Zeroes | EASY | 58.8 | 63% | Array · Two Pointers |
| 17 | Longest Substring Without Repeating Characters | MEDIUM | 58.8 | 37% | Hash Table · String · Sliding Window |
| 18 | Roman to Integer | EASY | 58.8 | 65% | Hash Table · Math · String |
| 19 | Best Time to Buy and Sell Stock | EASY | 58.8 | 55% | Array · Dynamic Programming |
| 20 | Reverse Words in a String III | EASY | 58.8 | 84% | Two Pointers · String |
| 21 | Longest Palindromic Substring | MEDIUM | 58.8 | 36% | Two Pointers · String · Dynamic Programming |
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 BNY Mellon OA. The proctor cannot see it. Screen share cannot detect it. Built by a senior engineer who knows the OA is theater. This is the script.
Get StealthCoder- array14 · 67%
- hash table7 · 33%
- string7 · 33%
- dynamic programming6 · 29%
- two pointers6 · 29%
- greedy5 · 24%
- sorting4 · 19%
- math3 · 14%
- prefix sum2 · 10%
- stack1 · 5%
Array problems dominate BNY Mellon's list, but they're not all the same shape. You'll see greedy-array hybrids (Gas Station, Minimum Taps to Water a Garden), array-plus-hash-table problems (Group Anagrams, Sum of Distances), and array-plus-dynamic-programming (Palindromic Substrings, Minimize Length of Array). Two-pointer and sorting tactics show up in at least 10 problems. The hard problems mix graph traversal, memoization, and combinatorics, but you won't face those until you've nailed the medium tier. String problems exist but they're secondary. Start with the greedy-array intersection, then move into hash-table lookups within arrays. If you get stuck on a medium array problem during the actual assessment, StealthCoder delivers a working solution in seconds while the proctor sees nothing.
Companies with similar patterns
If you prepped for BNY Mellon, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass BNY Mellon.
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 by a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
BNY Mellon interview FAQ
How many array problems should I solve before a BNY Mellon OA?+
At least 10 to 15, weighted toward medium difficulty. Two-thirds of reported problems involve arrays, and greedy tactics dominate. Hit Two Sum, Gas Station, Minimize Length of Array, and at least one medium DP-array hybrid. Six easy problems won't be enough to build the intuition.
Do I need to study graph algorithms for BNY Mellon?+
Only one reported problem is pure graph (Count Visited Nodes). But it's hard and uses memoization and DP together. If you're short on time, defer it. Nail the 14 array problems first. Graph shows up rarely enough that it's a tiebreaker, not a core skill.
What's the right order to study these topics?+
Start with arrays and two-pointers (3Sum, Two Sum, Car Fleet). Move into greedy-array (Gas Station, Minimum Taps). Then tackle hash-table (Group Anagrams, Count Vowel Substrings). Save DP and monotonic stack for your final week. 12 of 21 problems are medium, so drilling that tier pays off fastest.
Are string problems a priority for BNY Mellon?+
No. Only 7 of 21 reported problems involve strings, and most pair strings with hash tables or two-pointers. If you have 3 days left, focus on array-greedy and array-DP instead. String problems here are supporting acts, not leads.
What's the hardest gap between easy and medium problems?+
Easy problems like Two Sum use hash tables for O(n) solutions. Medium problems like Minimize Length of Array layer in math and greedy reasoning on top of the array manipulation. The jump requires you to think about problem properties (remainders, intervals, orderings) not just lookups. Budget extra time for that gap.