Find First and Last Position of Element in Sorted Array
A medium-tier problem at 47% community acceptance, tagged with Array, Binary Search. Reported in interviews at NetApp and 30 others.
You're in an OA and the problem looks simple: find the first and last position of a target in a sorted array. Your gut says linear scan. That's exactly why candidates miss it. The sorted array is the hint. Companies like Meta, LinkedIn, and Zillow ask this frequently, and the acceptance rate hovers just under 47%, which tells you the naive approach trips people up. Binary search is the pattern, but applying it twice to find both boundaries is where the logic breaks. If you hit this on assessment day and blank on the two-pass trick, StealthCoder surfaces the working solution in seconds, invisible to the proctor.
Companies that ask "Find First and Last Position of Element in Sorted Array"
Find First and Last Position of Element in 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. Built by an engineer who got tired of watching his cohort grind for six months and still get filtered at the OA stage.
Get StealthCoderThe trap is thinking one binary search finds both bounds. It doesn't. You need two separate binary searches: one to find the leftmost occurrence, one for the rightmost. Each search has slightly different termination logic. Most candidates code the first correctly, then botch the second boundary case or waste time on a manual sweep after finding any match. The array is sorted, so O(log n) is non-negotiable. The medium difficulty reflects that the concept is known but execution has sharp edges: off-by-one errors, incorrect comparison operators in the termination condition, and confusion about which direction to collapse the search window. If you haven't drilled this pattern recently, StealthCoder is your hedge for the moment the interview logic breaks under pressure.
Pattern tags
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Find First and Last Position of Element in Sorted Array 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 who got tired of watching his cohort grind for six months and still get filtered at the OA stage. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Find First and Last Position of Element in Sorted Array interview FAQ
Is this really asked at big companies?+
Yes. Meta, LinkedIn, Zillow, Splunk, NetApp and 26 others have reported it. It's a screening filter because it separates candidates who understand binary search edge cases from those who don't. Not a gimmick problem.
Why is acceptance rate so low if it's just binary search?+
Because two binary searches with different boundary logic isn't intuitive. Candidates find one boundary cleanly, then either overfetch with linear scan or code the second search wrong. The off-by-one bugs are silent and submission failures pile up.
Can I solve this with one binary search?+
Not cleanly without a linear scan after. You need two passes to find left and right boundaries independently. Trying to compress into one search usually breaks the logic or trades time complexity, which defeats the point.
What if the target isn't in the array?+
Return [-1, -1]. This is the edge case most people handle poorly. Your binary search must return consistent sentinel values when the target is absent, not crash or loop infinitely.
Is Array and Binary Search the only topics I need?+
Yes. No dynamic programming, no graphs, no hash maps. Pure algorithm. The topics list confirms it: this is about search strategy on a sorted structure, nothing more.
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