Medium data structure and algorithm practice puzzle.
Given room bookings as [start, end], find the first clash when the bookings are read in order of start time, and return the two booking numbers, smaller first. Return [] if nothing clashes. One booking can start right when another ends. The answer uses the ORIGINAL booking numbers, not their position after you reorder them.
Solve it three ways: snap the jigsaw pieces together, fill in the blanks, or type it from scratch against the tests. This one is free.
Every line of the solution comes with a note explaining why it is there, and a step by step replay shows the code running. At level 3, where you type it yourself, you can ask for an AI mock interview on this problem that ends with a hiring manager's scorecard.
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