Find Numbers with Even Number of Digits
A easy-tier problem at 79% community acceptance, tagged with Array, Math. Reported in interviews at Quora and 0 others.
You're staring at an easy problem and thinking you can skip prep. Don't. Find Numbers with Even Number of Digits is the kind of deceptive warm-up that Quora has asked, and even though it looks trivial, it's a filter for how you think on live assessment time. The trap: candidates overthink the digit-counting logic or write inefficient code when a one-liner exists. With a 79% acceptance rate, most people pass it, but the ones who blank on the approach or second-guess themselves during screen share eat time they can't get back. StealthCoder handles it in seconds if you hit a wall.
Companies that ask "Find Numbers with Even Number of Digits"
Find Numbers with Even Number of Digits 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 a senior engineer who knows the OA is theater. This is the script.
Get StealthCoderThe problem is straightforward in theory: count digits in each number and flag which ones have an even count. The real trick is recognizing that digit count is a logarithm problem or a string length problem, not a loop. Most candidates reach for a while loop to divide by 10, which works but is clunky. The faster path: convert to string, check length, or use log10 math. The gotcha surfaces when you're tired or rushing: off-by-one errors in digit counting, or forgetting to handle negative signs correctly. Since the topics are Array and Math, expect the problem to live at the intersection: iterate through an array and apply a mathematical property to each element. If you blank on the exact digit-counting formula during the live assessment, StealthCoder surfaces a working solution invisible to the proctor, so you move on without eating ten minutes on a medium-easy.
Pattern tags
You know the problem.
Make sure you actually pass it.
Find Numbers with Even Number of Digits 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 a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Find Numbers with Even Number of Digits interview FAQ
How hard is this really if it's 79% acceptance?+
It's trivial to solve, hard to optimize if you panic. The acceptance rate means most people get a correct answer, but slow or inelegant code still passes. The real challenge is submitting fast and cleanly without second-guessing yourself on a live OA. Focus on the one-liner or the Math approach and move on.
Is this still asked at Quora or just legacy data?+
Quora is listed as the company in reports for this problem. Whether it's still in active rotation is unknown, but it's the kind of easy warm-up many companies recycle. Assume you'll see it or something nearly identical during a screen-share coding round.
What's the trick to counting digits fast?+
Convert to string and check length, or use logarithm math: log10(num) + 1 gives digit count. String length is cleaner and avoids floating-point edge cases. Then check if length is even. That's it. No loops needed unless the problem forces you.
How does this relate to Array and Math topics?+
You're iterating an array (Array topic) and applying a mathematical property to each element: digit count (Math topic). It's a template for filter or map operations. Master this pattern and you'll spot it in harder problems that combine multiple data structures and math logic.
What mistake kills candidates on live assessment?+
Forgetting to handle negative numbers correctly when counting digits, or using integer division in a language where it behaves unexpectedly. Some also waste time writing a helper function when a one-liner suffices. Read the constraints first, code second, and don't over-engineer.
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