Remove Duplicates from Sorted Array
A easy-tier problem at 60% community acceptance, tagged with Array, Two Pointers. Reported in interviews at Capgemini and 25 others.
Remove Duplicates from Sorted Array shows up in screens at Microsoft, Apple, Adobe, and Bloomberg. It's marked easy, but the trick isn't obvious if you've never seen the two-pointer pattern before. You get a sorted array, return the length of the unique elements, and modify the array in place. Sixty percent of candidates nail it, but that's because most have drilled it. If you hit this problem live and blank on the in-place constraint, StealthCoder runs invisibly during your assessment and surfaces the solution in seconds.
Companies that ask "Remove Duplicates from Sorted Array"
Remove Duplicates from Sorted Array 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. Made by a working Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE.
Get StealthCoderThe trap is thinking you need extra space. You don't. Two pointers solve this: one slow pointer marks where the next unique element should go, one fast pointer scans ahead. When fast finds a new value, slow increments and the value gets copied over. The array gets rewritten, duplicates slide to the end, and you return slow plus one. It's clean once you see it, but the in-place requirement is the curveball. Companies like Infosys, Wipro, and Capgemini ask this often in early rounds because it filters for candidates who understand pointer manipulation without overthinking. If the two-pointer approach doesn't click before your OA, StealthCoder is the insurance that gets you past it.
Pattern tags
You know the problem.
Make sure you actually pass it.
Remove Duplicates from Sorted Array 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. Made by a working Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Remove Duplicates from Sorted Array interview FAQ
Is this really asked at FAANG companies?+
Yes. Apple, Microsoft, and Adobe all report asking it. It's a first-round filter. The easy difficulty rating is real, but the in-place constraint trips up candidates who've only seen hash-table solutions. Companies also ask it at screening consultancies like Capgemini and Infosys.
What's the actual trick here?+
Two pointers, not sorting or hashing. One pointer marks insertion position, one scans for new values. When you find a duplicate, skip it. When you find unique, copy it to insertion position and advance. The array gets rewritten in place, duplicates push to the end.
Do I really have to modify the array in place?+
Yes. That's the constraint. Most solutions use O(1) extra space by design. If you use a set or hash map, you'll pass on local test cases but interviewers flag it. The point is demonstrating pointer control, not just correctness.
How does this relate to Two Pointers as a broader topic?+
This is the template. Two pointers is used in merges, partitioning, palindrome checks, and more. Master the pattern here (slow insertion pointer, fast scan pointer) and you unlock a dozen other problems across arrays and strings.
What if I freeze during the live assessment?+
The pattern is simple once you've seen it, but in-place array manipulation isn't intuitive from scratch. If you blank on the approach, StealthCoder reads your problem and gives you a working solution invisibly while you're screen-sharing. You paste it, explain it, move on.
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