Medium data structure and algorithm practice puzzle.
Given a memory bitmap where 0 is a free page and 1 is used, and a number k, return the starting index of the first run of k free pages in a row, or -1 if there isn't one. Count free pages as you go, and reset the count on a used page. Lots of free memory doesn't help if it's split into pieces smaller than k.
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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