mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 05:21:09 +00:00
9316e7c014
* flake8 --max-line-length=88
* fixup! Format Python code with psf/black push
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
109 lines
3.6 KiB
Python
109 lines
3.6 KiB
Python
# Implementation of First Come First Served scheduling algorithm
|
|
# In this Algorithm we just care about the order that the processes arrived
|
|
# without carring about their duration time
|
|
# https://en.wikipedia.org/wiki/Scheduling_(computing)#First_come,_first_served
|
|
from typing import List
|
|
|
|
|
|
def calculate_waiting_times(duration_times: List[int]) -> List[int]:
|
|
"""
|
|
This function calculates the waiting time of some processes that have a
|
|
specified duration time.
|
|
Return: The waiting time for each process.
|
|
>>> calculate_waiting_times([5, 10, 15])
|
|
[0, 5, 15]
|
|
>>> calculate_waiting_times([1, 2, 3, 4, 5])
|
|
[0, 1, 3, 6, 10]
|
|
>>> calculate_waiting_times([10, 3])
|
|
[0, 10]
|
|
"""
|
|
waiting_times = [0] * len(duration_times)
|
|
for i in range(1, len(duration_times)):
|
|
waiting_times[i] = duration_times[i - 1] + waiting_times[i - 1]
|
|
return waiting_times
|
|
|
|
|
|
def calculate_turnaround_times(
|
|
duration_times: List[int], waiting_times: List[int]
|
|
) -> List[int]:
|
|
"""
|
|
This function calculates the turnaround time of some processes.
|
|
Return: The time difference between the completion time and the
|
|
arrival time.
|
|
Practically waiting_time + duration_time
|
|
>>> calculate_turnaround_times([5, 10, 15], [0, 5, 15])
|
|
[5, 15, 30]
|
|
>>> calculate_turnaround_times([1, 2, 3, 4, 5], [0, 1, 3, 6, 10])
|
|
[1, 3, 6, 10, 15]
|
|
>>> calculate_turnaround_times([10, 3], [0, 10])
|
|
[10, 13]
|
|
"""
|
|
return [
|
|
duration_time + waiting_times[i]
|
|
for i, duration_time in enumerate(duration_times)
|
|
]
|
|
|
|
|
|
def calculate_average_turnaround_time(turnaround_times: List[int]) -> float:
|
|
"""
|
|
This function calculates the average of the turnaround times
|
|
Return: The average of the turnaround times.
|
|
>>> calculate_average_turnaround_time([0, 5, 16])
|
|
7.0
|
|
>>> calculate_average_turnaround_time([1, 5, 8, 12])
|
|
6.5
|
|
>>> calculate_average_turnaround_time([10, 24])
|
|
17.0
|
|
"""
|
|
return sum(turnaround_times) / len(turnaround_times)
|
|
|
|
|
|
def calculate_average_waiting_time(waiting_times: List[int]) -> float:
|
|
"""
|
|
This function calculates the average of the waiting times
|
|
Return: The average of the waiting times.
|
|
>>> calculate_average_waiting_time([0, 5, 16])
|
|
7.0
|
|
>>> calculate_average_waiting_time([1, 5, 8, 12])
|
|
6.5
|
|
>>> calculate_average_waiting_time([10, 24])
|
|
17.0
|
|
"""
|
|
return sum(waiting_times) / len(waiting_times)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
# process id's
|
|
processes = [1, 2, 3]
|
|
|
|
# ensure that we actually have processes
|
|
if len(processes) == 0:
|
|
print("Zero amount of processes")
|
|
exit()
|
|
|
|
# duration time of all processes
|
|
duration_times = [19, 8, 9]
|
|
|
|
# ensure we can match each id to a duration time
|
|
if len(duration_times) != len(processes):
|
|
print("Unable to match all id's with their duration time")
|
|
exit()
|
|
|
|
# get the waiting times and the turnaround times
|
|
waiting_times = calculate_waiting_times(duration_times)
|
|
turnaround_times = calculate_turnaround_times(duration_times, waiting_times)
|
|
|
|
# get the average times
|
|
average_waiting_time = calculate_average_waiting_time(waiting_times)
|
|
average_turnaround_time = calculate_average_turnaround_time(turnaround_times)
|
|
|
|
# print all the results
|
|
print("Process ID\tDuration Time\tWaiting Time\tTurnaround Time")
|
|
for i, process in enumerate(processes):
|
|
print(
|
|
f"{process}\t\t{duration_times[i]}\t\t{waiting_times[i]}\t\t"
|
|
f"{turnaround_times[i]}"
|
|
)
|
|
print(f"Average waiting time = {average_waiting_time}")
|
|
print(f"Average turn around time = {average_turnaround_time}")
|