Lexicographically Smallest String After Operations With Constraint
A medium-tier problem at 62% community acceptance, tagged with String, Greedy. Reported in interviews at ServiceNow and 0 others.
Lexicographically Smallest String After Operations With Constraint is a medium-difficulty string problem that ServiceNow has asked. You're given a string and can perform operations under a specific constraint, and you need to find the lexicographically smallest result. The 62% acceptance rate tells you it's not trivial: most candidates know the greedy intuition, but miss edge cases or misunderstand the constraint mechanics. If this hits your live OA and you blank on the order of operations or when greedy fails, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "Lexicographically Smallest String After Operations With Constraint"
Lexicographically Smallest String After Operations With Constraint 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 trap here is assuming greedy always works. You want the smallest string lexicographically, so the naive instinct is to make the leftmost character as small as possible first. That fails because the constraint limits which swaps or transformations you can actually perform at each step. The real pattern is figuring out the scope of the constraint: does it allow you to pick any position, or does it bind you to a window. Once you map that, you build a greedy strategy that respects the constraint's boundaries. Most failures come from either ignoring the constraint entirely or applying it too rigidly and missing valid moves. StealthCoder is your hedge if you misread the constraint on day one and need a correct implementation fast.
Pattern tags
You know the problem.
Make sure you actually pass it.
Lexicographically Smallest String After Operations With Constraint 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 a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Lexicographically Smallest String After Operations With Constraint interview FAQ
Is this just a sorting problem wrapped in greedy language?+
No. If it were pure sorting, acceptance would be 90%+. The constraint prevents you from simply sorting the entire string. You're building the lexicographically smallest result step by step, respecting local limits on what you can swap or modify at each position.
What's the most common reason people fail this problem?+
Misreading or ignoring the constraint. Candidates solve for the globally optimal string without checking whether each operation is legal under the constraint. Re-read it twice before coding. The constraint is the whole problem.
Is string manipulation or greedy the harder part here?+
Greedy. String operations in most languages are straightforward. The hard part is proving your greedy choice is optimal and won't lock you out of better moves later. Work through a small example by hand before coding.
How often do companies ask constraint-based greedy string problems?+
Frequently, especially at companies building workflow or data systems like ServiceNow. They care whether you can optimize under real-world rules, not just theoretical limits. Expect variations in phone and onsite rounds.
Should I prioritize learning this problem or similar greedy patterns?+
Learn the pattern. Understand why greedy works here: at each step, what's the best move that doesn't violate the constraint? That thinking transfers to scheduling, interval, and resource-allocation problems across many companies.
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