Find the Shortest Superstring
A hard-tier problem at 44% community acceptance, tagged with Array, String, Dynamic Programming. Reported in interviews at DE Shaw and 0 others.
Find the Shortest Superstring is a hard-tier problem that hits your screen and immediately feels unsolvable. You're given an array of strings and need to find the shortest string that contains every input string as a substring. DE Shaw asks it. The naive approach is a dead end: there's no greedy sorting trick that works, and brute force will timeout. The real solution lives in the intersection of dynamic programming and bitmask state compression. If you haven't seen this pattern before, you'll blank during the live OA. StealthCoder is your safety net for the one problem you didn't drill.
Companies that ask "Find the Shortest Superstring"
Find the Shortest Superstring 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 a senior engineer who knows the OA is theater. This is the script.
Get StealthCoderThe trick is modeling this as a traveling salesman variant where each string is a node, overlap between pairs is the edge weight, and you want the shortest path visiting all nodes exactly once. You use a bitmask to track which strings you've included and a DP table where dp[mask][last_string] stores the shortest superstring built from that subset, ending with that specific string. The common failure is not precomputing overlaps between every pair of strings upfront, or conflating substring containment with the order constraint. Most candidates either miss that some input strings are substrings of others (and can be removed), or they implement the DP transitions incorrectly and timeout. The math is clean once you see it, but the pattern is not obvious without prior exposure. This is exactly where StealthCoder surfaces a working solution in seconds if the trick escapes you.
Pattern tags
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Make sure you actually pass it.
Find the Shortest Superstring 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 by a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Find the Shortest Superstring interview FAQ
How hard is this really compared to other hard DP problems?+
It ranks in the top 10% of hard problems. Acceptance sits at 44%, which reflects the gap between understanding DP and recognizing bitmask TSP variants. Most people see 'shortest string' and attempt greedy, which fails. It's not about coding speed, it's about pattern recognition.
Do I need to know about the traveling salesman problem to solve this?+
Not by name, but the structure is identical. You're finding an optimal tour through nodes where the cost is edge overlap, not distance. If you've seen TSP with bitmask DP, this becomes familiar. Otherwise, it's a aha moment under pressure.
What's the trap that kills submissions?+
Forgetting to check if any input string is a substring of another and remove it first. Also, incorrect overlap calculation: overlaps go both directions (A overlaps with B and vice versa). The DP transition is also easy to mess up if you're not careful about indexing the mask and last string state.
Is there a way to reduce this to a simpler problem?+
Not really. You can remove redundant strings (those contained in others), which shrinks the input. But the core is still bitmask DP on the remaining strings. There's no shortcut that avoids exploring all permutation orderings.
Why does DE Shaw ask this?+
It's not a gimme. They're testing if you can spot an advanced DP pattern, handle bitmask operations, and implement state compression cleanly under time pressure. It signals strong algorithmic thinking and composure on a problem you likely haven't seen before.
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