Divide a String Into Groups of Size k
A easy-tier problem at 67% community acceptance, tagged with String, Simulation. Reported in interviews at Canonical and 0 others.
You're asked to split a string into chunks of exactly k characters, padding the last group if needed. It's an easy problem that shows up in real assessments, and Canonical has asked it. The trap isn't the algorithm, it's handling the edge case where your final group falls short of k characters. Most candidates nail the happy path and then fumble the padding logic during the actual assessment. If you blank on how to construct that last partial group, StealthCoder runs invisibly and surfaces the working solution in seconds.
Companies that ask "Divide a String Into Groups of Size k"
Divide a String Into Groups of Size k 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 pattern is straightforward: iterate through the string in steps of k, slice out each substring, and append it to your result. The gotcha is what happens when len(string) isn't divisible by k. You need to pad the last group with a character (usually 'x') until it reaches length k. Candidates often try to overthink this with modulo arithmetic or conditional branches that break under different padding rules. The real trick is recognizing that you can just check if the last group is shorter than k and pad it after your loop finishes. String slicing makes this almost invisible. This is a Simulation problem that tests attention to detail, not algorithmic depth. If you hit this live and your padding logic crumbles, StealthCoder solves it without the proctor seeing a thing.
Pattern tags
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Make sure you actually pass it.
Divide a String Into Groups of Size k 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.
Divide a String Into Groups of Size k interview FAQ
How hard is this problem really?+
It's genuinely easy. The acceptance rate is 67%, which means most people pass. The challenge isn't the core logic but handling the last group padding correctly. If you understand string slicing and basic loops, you're 90% there.
What's the trick I'm missing?+
There's no deep trick. The pitfall is forgetting that the final group might be incomplete and needs padding. Write your loop to extract groups of k, then check if the last group is shorter than k and pad it. That's it.
Do I really need to worry about this if it's just marked easy?+
Yes. Easy problems in live assessments are still pass-or-fail gates. A 67% acceptance rate means 1 in 3 people either time out, miss the padding, or write brittle code. It's the kind of thing you forget under interview pressure.
How does this relate to the String and Simulation topics?+
String is obvious: you're manipulating substrings. Simulation means you're stepping through the string character by character (or in chunks) and building output. No fancy data structures or recursion needed.
Is this still asked at real companies?+
Canonical has asked it. Easy problems like this appear across most companies as warm-up or screening questions. They're less common in later interview rounds but still a real gate at the early stage.
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