To Lower Case
A easy-tier problem at 84% community acceptance, tagged with String. Reported in interviews at Infosys and 0 others.
To Lower Case is the warm-up problem that catches overconfident candidates. With an 84% acceptance rate, it looks trivial, but the trick isn't obvious until you're live on the assessment and realize you've written three lines when one would do. Infosys includes it in their technical screening, and it's the kind of problem where a clean, idiomatic solution signals you know your language cold. If you blank on the built-in method or mishandle edge cases like digits and special characters, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "To Lower Case"
To Lower Case 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 problem asks you to convert a string to lowercase. The naive trap is writing a loop and manually converting each character, which works but screams that you're unfamiliar with standard library functions. The real pattern is knowing that every major language has a built-in lowercase method, and the edge case is understanding what that method leaves untouched: digits, punctuation, and whitespace stay exactly as they are. The algorithm is trivial, but candidates often overcomplicate it by trying to iterate character-by-character or by handling ASCII codes manually. Since this is an easy String problem with high acceptance, the assessment is testing whether you reach for the right tool immediately. If you find yourself stuck on the implementation details during your live OA, StealthCoder delivers the one-liner you need.
Pattern tags
You know the problem.
Make sure you actually pass it.
To Lower Case 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.
To Lower Case interview FAQ
Is this really asked at tech companies, or is it just a warm-up?+
Infosys includes it in their screening loop. At that level, it's often a warm-up to settle your nerves and establish baseline confidence. The acceptance rate of 84% confirms most candidates pass it, so it's more about execution speed and code cleanliness than algorithmic depth.
What's the trick I'm missing if my solution works but feels too simple?+
There is no trick. The trick is recognizing there's no trick and using the language's built-in method directly. Common misstep: candidates implement manual ASCII conversion or loop through each character, adding lines for no reason. One method call, done.
How does this relate to broader string problems?+
It tests whether you know your language's standard library and can implement character transformation correctly. More complex string problems build on this foundation, so a clean solution here sets up good habits for harder String-topic problems.
Will this problem stall me if I haven't seen it before?+
Unlikely, but edge cases can trip you up: mixed case, numbers, punctuation, empty strings. If you're unsure about what your language's lowercase method actually does or returns, you might waste time on the assessment. That's where pre-flight clarity matters.
What language-specific gotchas should I watch for?+
Python has str.lower(), JavaScript has toLowerCase(), Java has toLowerCase(). Know your language's exact method name and return type before the assessment. Some languages return a new string; others mutate in place. Confirm your language's behavior now, not live.
Want the actual problem statement? View "To Lower Case" on LeetCode →