FCFS Scheduling

import operator

# Process class to store process details
class Process:
    def __init__(self, process_id, arrival_time, burst_time):
        self.process_id = process_id
        self.arrival_time = arrival_time
        self.burst_time = burst_time

    def __str__(self):
        return f"Process ID: {self.process_id}, Arrival Time: {self.arrival_time}, Burst Time: {self.burst_time}"

# Function to calculate the waiting time of each process
def find_waiting_time(processes, n):
    # Sort processes based on their arrival time
    processes.sort(key=operator.attrgetter('arrival_time'))

    # Create a list to store the waiting time of each process
    waiting_time = [0] * n

    # Initialize variables for current time, completed processes and remaining processes
    current_time = processes[0].arrival_time
    completed = 0
    remaining_processes = processes[:]

    # Loop until all processes are completed
    while completed < n:
        # Sort the remaining processes based on their burst time
        remaining_processes.sort(key=operator.attrgetter('burst_time'))

        # Get the process with shortest burst time
        shortest_process = remaining_processes.pop(0)

        # Calculate waiting time of the shortest process
        waiting_time[shortest_process.process_id - 1] = current_time - shortest_process.arrival_time

        # Update current time and completed processes
        current_time += shortest_process.burst_time
        completed += 1

    return waiting_time

# Function to calculate the average waiting time of all processes
def find_average_waiting_time(processes, n):
    waiting_time = find_waiting_time(processes, n)

    # Calculate the total waiting time of all processes
    total_waiting_time = sum(waiting_time)

    # Calculate and return the average waiting time
    return total_waiting_time / n

# Sample input data
processes = [Process(1, 0, 6), Process(2, 1, 8), Process(3, 2, 7), Process(4, 3, 3)]

# Calculate and print the average waiting time
avg_waiting_time = find_average_waiting_time(processes, len(processes))
print(f"Average Waiting Time: {avg_waiting_time}")