Medium data structure and algorithm practice puzzle.
Given an array and k, return the kth largest value, where k = 1 means the biggest. Duplicates count separately. Sort from biggest to smallest and take the item at position k - 1. That's O(n log n). Follow-ups: a min-heap of size k does it in O(n log k), and quickselect averages O(n).
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 Sample Calibrator, a pipeline you can run and download. See every Software Engineer project.
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