Weighted round-robin task scheduler

Python data engineering interview problem. Difficulty: advanced. Pattern: Streaming. About 20 minutes. Part of the Pro drill bank.

A task scheduler should pick workers in weighted round-robin so a worker with twice the weight gets roughly twice the jobs.

Simulate weighted round-robin assignment for a number of steps.

Requirements

• Higher weight means more frequent picks.
• The sequence length equals steps.

Constraints

• workers: names with weights.
• steps: how many assignments to emit.
• A weight of 0 should never be picked.
• One worker takes every step if it is the only positive weight.

Examples

Input: weighted_round_robin([('a', 2), ('b', 1)], 5) Output: ['a', 'a', 'b', 'a', 'a'] This input follows the stated rules and produces this output.

Topics: lakebench, python, queue.

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