The k largest numbers in Java
Java interview exercise on Collections, difficulty 2 of 3. Solve it in the editor beside a worked example; the tests run the moment you do.
Write topK(nums, k) that returns the k largest numbers in descending order, keeping only k numbers in memory at a time: a min-heap (PriorityQueue) of size k whose smallest element is dropped whenever a bigger number arrives. If k is larger than the list, return everything sorted descending; k = 0 gives an empty list.
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