The purpose of this project is to write a program
 (use any programming language) that simulates an operating system. 

The program implements the following CPU scheduling algorithms. 

1.      First-Come-First-Serve (FCFS)
2.      Shortest-Job-First (SJF)
3.      Round-Robin with time slice = 3 (RR-3)
4.      Round-Robin with time slice = 5 (RR-5)

The program will read process burst times from a file (job.txt) -
 this file will be provided by the instructor. 

A sample input file of four jobs is given as follows (burst time in ms).:
[Begin of job.txt]
Job1
6
Job2
4
Job3
10
Job4
7
[End of job.txt]

Note: You can assume that
(1)      there are no more than 30 jobs in the input file (job.txt).
(2)      processes arrive in the order they are read from the 
file for FCFS, RR-3 and RR-5.
(3)      all jobs arrive at time 0 for SJF.


Compare the average completion times of all jobs for each 
scheduling algorithm. 
Output the details of each algorithm's execution. You need
to show which jobs are selected at what 
times as well as their starting and stopping burst values. 
You can choose your display format, 
but it is recommended that you display the results in 
terms of a Gantt chart.