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Top K in Streaming
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Top K in Streaming

MediumPython

Problem

How do you find the top K elements in streaming data, optimizing for time complexity better than a heap-based approach?

Asked in the Phone Screen stage. The interviewer was dissatisfied with the standard heap solution, prompting the candidate to suggest a bucket-based method for O(1) time complexity.

Task

Implement top_k_stream(stream, k, max_value). The stream contains integers from 0 through max_value. Return the largest k values in descending order, preserving duplicates. Use a bucket or direct-address counting strategy. The input guarantees 1 <= k <= len(stream).

Constraints

  • 1 <= len(stream) <= 1000
  • 1 <= k <= len(stream)
  • 0 <= max_value <= 10000
  • 0 <= stream[i] <= max_value

Function Signature

def top_k_stream(stream, k, max_value):
Interviewer

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Code
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