#### Round Robin

```"""
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__ import annotations

from statistics import mean

def calculate_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 =  * len(burst_times)
t = 0
while True:
done = True
for i, burst_time in enumerate(burst_times):
if rem_burst_times[i] > 0:
done = False
if rem_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
if done is True:
return waiting_times

def calculate_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 + waiting for burst, waiting in zip(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")
for i, burst_time in enumerate(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}")
```  