Height Checker
A easy-tier problem at 81% community acceptance, tagged with Array, Sorting, Counting Sort. Reported in interviews at Salesforce and 1 others.
Height Checker is an easy-difficulty problem that shows up in real assessments at Salesforce and IBM. It has an 81% acceptance rate, which sounds safe until you realize the easy problems are where candidates blank on the sorting pattern. You read the problem, think "I'll just sort it," start coding, and lose 10 minutes on implementation details. If this one hits your live OA and you freeze on the mechanics, StealthCoder surfaces a working solution in seconds, invisible to the proctor. It's the hedge for the problem you didn't drill.
Companies that ask "Height Checker"
Height Checker 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 an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share.
Get StealthCoderThe problem asks you to compare students' actual heights against their sorted heights and count mismatches. The trap: thinking you need a complex data structure to track positions. The pattern is simpler. Sort the heights, compare element by element, count differences. Most candidates overcomplicate it with maps or index tracking when a basic sort-and-compare does the job. The trick is recognizing this falls under Counting Sort territory, not general sorting, which means you can optimize space if needed. StealthCoder matters here because the obvious solution works but candidates second-guess themselves on whether it's efficient enough. During a live assessment, that doubt costs minutes.
Pattern tags
You know the problem.
Make sure you actually pass it.
Height Checker recycles across companies for a reason. It's easy-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 an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Height Checker interview FAQ
Is Height Checker really that common in FAANG interviews?+
It shows up at Salesforce and IBM in real reports. It's an easy problem so companies use it as a warm-up or screening filter. You'll see it less often than hard problems, but if it appears, high acceptance rate means everyone should solve it. Missing it tanks your confidence.
What's the actual trick to Height Checker?+
There isn't a hidden trick. Sort the original array, compare each element to the sorted version, count mismatches. The real trap is overthinking it with extra data structures. Candidates waste time on index mapping when a straightforward comparison works perfectly.
Should I use Counting Sort for this or just Arrays and Sorting?+
Both work. Standard sort (Arrays, Sorting topics) is fast enough for interview constraints. Counting Sort is optimal if heights are bounded small integers, but most online assessments don't require it. Know both approaches, start with standard sort, mention counting optimization if you finish early.
How does Height Checker relate to other easy array problems?+
It's a one-liner pattern: sort and compare. Unlike harder array problems that chain multiple concepts, this teaches you to recognize when sorting alone solves the problem. It's the simplest version of array transformation logic.
Can I fail Height Checker even though it's easy?+
Yes. Time pressure makes even easy problems hard. You sort, start comparing, make an off-by-one error, debug under stress, run out of time. That's where StealthCoder works: you glance at a working solution and paste it, no proctor visibility.
Want the actual problem statement? View "Height Checker" on LeetCode →