round_robin.py

"""
Round Robin is a scheduling algorithm.
In Round Robin each process is assigned a fixed time slot in a cyclic way.
https://en.wikipedia.org/wiki/Round-robin_scheduling
"""

from __future__ importannotations

fromstatisticsimportmean


defcalculate_waiting_times(burst_times: list[int]) ->list[int]:
"""
 Calculate the waiting times of a list of processes that have a specified duration.

 Return: The waiting time for each process.
 >>> calculate_waiting_times([10, 5, 8])
 [13, 10, 13]
 >>> calculate_waiting_times([4, 6, 3, 1])
 [5, 8, 9, 6]
 >>> calculate_waiting_times([12, 2, 10])
 [12, 2, 12]
 """
quantum=2
rem_burst_times=list(burst_times)
waiting_times= [0] *len(burst_times)
t=0
whileTrue:
done=True
fori, burst_timeinenumerate(burst_times):
ifrem_burst_times[i] >0:
done=False
ifrem_burst_times[i] >quantum:
t+=quantum
rem_burst_times[i] -=quantum
else:
t+=rem_burst_times[i]
waiting_times[i] =t-burst_time
rem_burst_times[i] =0
ifdoneisTrue:
returnwaiting_times


defcalculate_turn_around_times(
burst_times: list[int], waiting_times: list[int]
) ->list[int]:
"""
 >>> calculate_turn_around_times([1, 2, 3, 4], [0, 1, 3])
 [1, 3, 6]
 >>> calculate_turn_around_times([10, 3, 7], [10, 6, 11])
 [20, 9, 18]
 """
return [burst+waitingforburst, waitinginzip(burst_times, waiting_times)]


if__name__=="__main__":
burst_times= [3, 5, 7]
waiting_times=calculate_waiting_times(burst_times)
turn_around_times=calculate_turn_around_times(burst_times, waiting_times)
print("Process ID \tBurst Time \tWaiting Time \tTurnaround Time")
fori, burst_timeinenumerate(burst_times):
print(
f" {i+1}\t\t{burst_time}\t\t{waiting_times[i]}\t\t "
f"{turn_around_times[i]}"
 )
print(f"\nAverage waiting time = {mean(waiting_times):.5f}")
print(f"Average turn around time = {mean(turn_around_times):.5f}")