Write a C program to implement the FCFS (FIRST COME FIRST SERVE) scheduling algorithm

Description:

First-come, first-serve scheduling (FCFS):

In this, which process enter the ready queue first is served first. The OS maintains DS that is ready queue. It is the simplest CPU scheduling algorithm. If a process requests the CPU then it is loaded into the ready queue, which process is the head of the ready queue, connect the CPU to that process.
Algorithm for FCFS scheduling:
Step 1: Start the process
Step 2: Accept the number of processes in the ready Queue
Step 3: For each process in the ready Queue, assign the process id and accept the CPU burst time
Step 4: Set the waiting of the first process as ‘0’ and its burst time as its turnaround time
Step 5: for each process in the Ready Queue calculate
(a) Waiting time for process (n)= waiting time of process (n-1) + Burst time of process(n-1)
(b)Turn around time for Process (n)= waiting time of Process(n)+ Burst time for process(n)
Step 6: Calculate
(c) Average waiting time = Total waiting Time / Number of process
(d)Average Turnaround time = Total Turnaround Time / Number of process
Step 7: Stop the process


#include<stdio.h>
int main()
{
int n,a[10],b[10],t[10],w[10],g[10],i,m;
float att=0,awt=0;
            for(i=0;i<10;i++)
            {
                        a[i]=0; b[i]=0; w[i]=0; g[i]=0;
            }
printf("enter the number of process");
            scanf("%d",&n);
printf("enter the burst times");
            for(i=0;i<n;i++)
                scanf("%d",&b[i]);
    printf("\nenter the arrival times");
            for(i=0;i<n;i++)
                scanf("%d",&a[i]);
    g[0]=0;
             for(i=0;i<10;i++)
                   g[i+1]=g[i]+b[i];
             for(i=0;i<n;i++)
            {   
w[i]=g[i]-a[i];
                        t[i]=g[i+1]-a[i];
                        awt=awt+w[i];
                        att=att+t[i];
            }
     awt =awt/n;
            att=att/n;
            printf("\n\tprocess\twaiting time\tturn arround time\n");
            for(i=0;i<n;i++)
            {
                        printf("\tp%d\t\t%d\t\t%d\n",i,w[i],t[i]);
            }
printf("the average waiting time is %f\n",awt);
printf("the average turn around time is %f\n",att);
return 0;
}

OUTPUT:
enter the number of process 4
enter the burst times
4  9  8  3
enter the arrival times
0  2  4  3
        process        waiting time     turn arround time
            p0                       0                          4
            p1                       2                         11
            p2                       9                         17
            p3                      18                        21
the average waiting time is 7.250000
the average turn around time is 13.250000

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