Sqrt(x)
A easy-tier problem at 40% community acceptance, tagged with Math, Binary Search. Reported in interviews at Grammarly and 20 others.
Sqrt(x) looks deceptively simple on the surface, but it trips up candidates who overthink it or lock onto the wrong approach. Asked by Apple, Amazon, TikTok, Uber, and Bloomberg, this easy-rated problem has a 40% acceptance rate, which means solid engineers are blanking on it in live assessments. The trap is obvious: you could just call a built-in function or brute-force every integer up to n. The real test is whether you recognize this as a binary search problem and implement clean bounds without off-by-one errors. If you hit this during your OA and the trick doesn't click, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "Sqrt(x)"
Sqrt(x) 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 an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoderThe algorithmic pattern here is binary search on a monotonic function. You're not searching a pre-sorted array; you're searching the space of integers from 0 to x, and the square root is the boundary where value squared stops being less than or equal to x. Most candidates either try Newton's method (overengineered for easy-rated), hardcode a loop (slow on large x), or mishandle the final answer by picking the wrong endpoint. The trick is tight bounds: search while left <= right, and track the last valid mid where mid * mid <= x, because the answer is always that largest valid integer, not the next one. One more pitfall: don't compute mid * mid on very large integers without checking for overflow, though Python handles it. When you're stuck in the assessment and time's slipping, StealthCoder runs invisibly and hands you the binary search skeleton with correct boundary logic.
Pattern tags
You know the problem.
Make sure you actually pass it.
Sqrt(x) 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 an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Sqrt(x) interview FAQ
Is this really an easy problem if 40% of people fail it?+
The acceptance rate reflects both wrong approach selection (brute force) and off-by-one errors on boundaries. Easy difficulty means the pattern is teachable in minutes, not that execution is automatic under pressure. Most failures are logic mistakes, not algorithmic ignorance. Nail the binary search bounds and you're done.
Do I need Newton's method or can I just use binary search?+
Binary search is the expected solution on this problem. Newton's method works but signals over-engineering. The problem tests whether you recognize a monotonic search space, not floating-point math. Stick with integer binary search for clarity and correctness.
Why do Amazon and Apple ask this if it's marked easy?+
It's not about difficulty; it's about screening for sloppy thinking. These companies ask it early in loops to disqualify candidates who can't implement basic algorithms cleanly. If you panic or rush, boundary logic breaks. It's a confidence and precision filter.
What's the trick to getting the right answer vs. off-by-one?+
Always track the last valid candidate (the largest integer whose square is less than or equal to x). Search while left <= right, update answer when mid * mid <= x, then move right or left. The answer is that tracked value, not mid on exit.
Does this relate to other binary search problems or Math problems?+
Yes, it's a bridge between the two topics. It teaches binary search on a continuous monotonic function without requiring a pre-sorted array. If you master boundary logic here, you'll handle search-on-answer and other implicit-space problems faster.
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