Minimum Time Difference
A medium-tier problem at 62% community acceptance, tagged with Array, Math, String. Reported in interviews at Palantir Technologies and 3 others.
Minimum Time Difference asks you to find the smallest gap between any two times in a list. It sounds simple until you realize times wrap around at midnight, and a naive sort misses the critical edge case. Companies like Palantir, Visa, Zoho, and Carwale have asked it. The trick isn't complex, but you need to spot it fast. If you blank on the wraparound logic during your live OA, StealthCoder surfaces the solution in seconds without the proctor seeing a thing.
Companies that ask "Minimum Time Difference"
Minimum Time Difference 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 treating times like regular numbers. Sort the times as strings or integers, but the real work happens after: you compare each consecutive pair, then check the wraparound from the last time back to the first (accounting for the 24-hour cycle). Many candidates code the sequential comparisons, forget the wraparound, and their answer fails half the test cases. Convert times to minutes for easier math, sort them, then iterate through gaps. The wraparound gap is 1440 minus (last time minus first time). This is a 62% acceptance rate problem because the wraparound catches people off guard in the live setting. If you've drilled this pattern, it's trivial. If you haven't, StealthCoder is your hedge.
Pattern tags
You know the problem.
Make sure you actually pass it.
Minimum Time Difference 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.
Minimum Time Difference interview FAQ
Why does the naive sort approach fail?+
Sorting alone doesn't account for the wraparound at midnight. You must calculate the gap from the last time back to the first time (1440 - last + first), then compare it to all consecutive gaps. Without that wraparound check, you'll get a wrong answer on test cases where the minimum gap crosses midnight.
Is this problem still asked at companies like Visa and Palantir?+
Yes. Both companies remain in the active report for this problem. It's a medium-difficulty classic, so it appears regularly in screens where they want to filter for clean implementation and edge-case thinking without requiring heavy algorithmic knowledge.
What's the trick to solving this quickly in an interview?+
Convert all times to minutes (single integer), sort them, loop through consecutive pairs to find gaps, then manually check the wraparound gap. Three lines of logic once you sort. The speed comes from recognizing the wraparound as a separate comparison, not trying to brute-force all pairs.
Should I use a string sort or integer sort?+
Convert to minutes (integers) first. String sort will fail because '9:00' sorts after '10:00' lexicographically. Integer sort on total minutes is cleaner and avoids that pitfall entirely. Also makes gap math trivial.
How does this relate to the Array and Sorting topics?+
The core pattern is sort-then-iterate. You're sorting an array and looking for properties of adjacent elements. Math topic covers the minute conversion and wraparound gap formula. It's a good test of whether you can combine multiple topics in one clean solution.
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