Compare Version Numbers
A medium-tier problem at 42% community acceptance, tagged with Two Pointers, String. Reported in interviews at Nextdoor and 5 others.
Version number comparison sounds trivial until you hit the edge cases in a live OA. This medium-difficulty string problem appears in assessments at Nextdoor, Zoho, ByteDance, TikTok, Cisco, and Apple. The acceptance rate sits at 42%, which means almost 6 in 10 candidates either miss the parsing logic or blow the comparison. You'll be given two version strings like '1.0' and '1.0.0' and asked which is larger, equal, or smaller. The trap is that trailing zeros matter less than you think, and a naive split-and-compare fails fast. If you blank on the two-pointer approach during your OA, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "Compare Version Numbers"
Compare Version Numbers 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 core trick is comparing version numbers segment by segment, where each segment is a number separated by a dot. The obvious move is to split both strings, pad to equal length, and compare. But the real pattern is a two-pointer approach that walks through both strings simultaneously, parsing each segment on the fly. You extract the next integer from each version string, compare them, and move past the dots. This avoids string allocation and handles variable-length versions cleanly. Common pitfall: forgetting that '1.0' and '1.0.0' are equal because trailing zero segments don't count. Another trap: parsing segments as strings instead of integers, which breaks the comparison. The two-pointer technique also scales if either version string is exhausted early, you treat missing segments as zero. During a live assessment, if this problem hits and you're unsure whether to pad or parse, StealthCoder gives you the clean integer-by-integer walk-through.
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Compare Version Numbers 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 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.
Compare Version Numbers interview FAQ
How hard is this really compared to other medium problems?+
The 42% acceptance rate suggests it's on the harder end of medium. It's not about complex algorithms but about handling string parsing and edge cases cleanly. Most failures come from missing the trailing-zero rule or writing brittle split logic, not from algorithmic insight.
Why do Nextdoor, Apple, and ByteDance ask this so often?+
Version comparison is a real backend problem. These companies need developers who can write clean, bug-free string parsing code without over-engineering. It's a signal of attention to detail and ability to handle fiddly input validation.
What's the trick to getting this right on the first try?+
Use two pointers, not split and pad. Walk through both strings at the same time, extract integers for each segment, compare them, and skip the dots. This avoids off-by-one errors and makes the trailing-zero case natural.
How does this relate to the Two Pointers topic?+
Two pointers means one pointer per version string. You move each pointer forward past the next segment, handling variable-length versions and mismatched lengths without extra arrays. It's a cleaner alternative to splitting.
Will this problem still show up in live OAs?+
Yes. Six major companies report it, including tier-1 names like Apple and ByteDance. The 42% acceptance rate means it's still a filter question, not a gimmick. It's worth drilling before an OA.
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