Medium data structure and algorithm practice puzzle.
A row of seats is part booked (1) and part free (0). Groups arrive in order, and each group has to sit together in one unbroken block. Seat each group in the leftmost free block that fits, and if none fits, they leave. Return how many groups get seated. Watch how the free seats get chopped into pieces too small to use.
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.
Then grow it into a real project with the Software Engineer button: this puzzle becomes the Reading Stream Buffer, a pipeline you can run and download. See every Software Engineer project.
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