def earliest_meeting_slot(events: list[str], k: int) -> str:
You are given a list of n event strings, events, and an integer k, the length of a meeting in minutes. Each event has the format
<name> <activity> <start> <end>
with times written as HH:MM, for example "Taylor sleep 00:00 08:00".
Find the earliest time at which everyone who appears in the events is free for at least k minutes, and return that start time as a string in "HH:MM" format. If there is no such time, return "-5".
"-5" is as reported; it is unusual, so confirm it."Taylor sleep 00:00 08:00"?)Five reports from 2025, the earliest from an OA taken in December 2024; four of them are for Citadel's NXT roles. They describe the same online assessment format: about 15 multiple-choice questions followed by one coding problem. The multiple-choice questions they list cover complexity comparisons (three solutions to one problem, which is fastest), picking the right fix for a buggy snippet, operating systems and networking basics, and system design topics such as push vs pull, message queues, NoSQL, forward vs reverse proxies and write-back vs write-through caching.
The May 2025 report gives the coding problem in detail, as in the statement above. Three other reports identify their coding problem as the widely shared earliest meeting time, or meeting scheduler, problem. A fifth report of the same assessment format says its coding problem was LeetCode 56 (Merge Intervals) in a wrapper with extra input and output handling, and does not connect it to this meeting-scheduler problem.
Outcomes vary. One candidate passed every visible test case with 15 minutes left, and the recruiter said the next morning they would not move forward. Another, who had practised the problem, had one test case fail and was still invited to the technical interviews. The reports do not say which cases failed. No report gives input limits or a sample with its expected answer.
You are given a list of n event strings, events, and an integer k, the length of a meeting in minutes. Each event has the format
<name> <activity> <start> <end>
with times written as HH:MM, for example "Taylor sleep 00:00 08:00".
Find the earliest time at which everyone who appears in the events is free for at least k minutes, and return that start time as a string in "HH:MM" format. If there is no such time, return "-5".
"-5" is as reported; it is unusual, so confirm it."Taylor sleep 00:00 08:00"?)Why people fail: One candidate passed every visible test case with 15 minutes left and was not moved forward; they suspected hidden cases.; One candidate who had practised the problem still had one test case fail.
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