Queue Length Forecast Lite

Problem

Forecast a deterministic fluid queue: each period the queue becomes max(0, queue + arrival_rate - service_rate). Return the queue length after each of the given periods, starting from initial_queue.

A negative queue is clipped to 0.

Hint

When service exceeds arrivals the queue drains, but never below zero.

Test cases

case 1

in: [3,2,0,4]

expected: [1,2,3,4]

case 2

in: [1,3,5,4]

expected: [3,1,0,0]

case 3

in: [2,2,10,2]

expected: [10,10]

case 4

in: [0,1,0,3]

expected: [0,0,0]

Starter codePython

def queue_length_forecast_lite(arrival_rate, service_rate, initial_queue, periods):
    # Your code here
    pass

4 test cases · run your code against them in the editor