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Live Coding System Design
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Live Coding System Design

HardPython

Problem

Describe how you would approach a live coding system design problem, including how you would structure the solution, choose data structures, and ensure correctness.

Implement the core queue component as process_operations(operations). Each operation is ['add', task_id, priority], ['cancel', task_id], or ['pop']; return the task IDs produced by pop operations, using None when the queue is empty. Lower priority values are dequeued first, and equal priorities use insertion order.

Constraints

  • 1 <= operations.length <= 500
  • Each operation is a valid add, cancel, or pop operation
  • Task IDs are strings
  • Priority values are integers
  • An active task ID is not added twice without first being cancelled or popped
  • Cancellation of a missing task has no effect

Function Signature

def process_operations(operations):
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