Round Robin Scheduling Algorithm

#include<stdio.h>
struct process
{
    int id,AT,BT,WT,TAT;
};
struct process a[10];
// declaration of the ready queue
int queue[100];
int front=-1;
int rear=-1;
// function for insert the element 
// into queue
void insert(int n)
{
    if(front==-1)
     front=0;
    rear=rear+1;
    queue[rear]=n;
}
// function for delete the 
// element from queue
int delete()
{
    int n;
    n=queue[front];
    front=front+1;
    return n;
}
int main()
{
    int n,TQ,p,TIME=0;
    int temp[10],exist[10]={0};
    float total_wt=0,total_tat=0,Avg_WT,Avg_TAT;
    printf("Enter the number of the process\n");
    scanf("%d",&n);
    printf("Enter the arrival time and burst time of the process\n");
    printf("AT BT\n");
    for(int i=0;i<n;i++)
    {
        scanf("%d%d",&a[i].AT,&a[i].BT);
        a[i].id=i;
        temp[i]=a[i].BT;
    }
    printf("Enter the time quantum\n");
    scanf("%d",&TQ);
    // logic for round robin scheduling
    
    // insert first process
    // into ready queue
    insert(0);
    exist[0]=1;
    // until ready queue is empty
    while(front<=rear)
    {
        p=delete();
        if(a[p].BT>=TQ)
        {
            a[p].BT=a[p].BT-TQ;
            TIME=TIME+TQ;
        }
        else
        {
            TIME=TIME+a[p].BT;
            a[p].BT=0;
        }
        
        
        //if process is not exist 
        // in the ready queue even a single 
        // time then insert it if it arrive
        // at time 'TIME'
        for(int i=0;i<n;i++)
        {
            if(exist[i]==0 && a[i].AT<=TIME)
            {
                insert(i);
                exist[i]=1;
            }
        }
        // if process is completed
        if(a[p].BT==0)
        {
            a[p].TAT=TIME-a[p].AT;
            a[p].WT=a[p].TAT-temp[p];
            total_tat=total_tat+a[p].TAT;
            total_wt=total_wt+a[p].WT;
        }
        else
        {
            insert(p);
        }
    }
    
    Avg_TAT=total_tat/n;
    Avg_WT=total_wt/n;
    
    // printing of the answer
    printf("ID WT TAT\n");
    for(int i=0;i<n;i++)
    {
        printf("%d  %d  %d\n",a[i].id,a[i].WT,a[i].TAT);
    }
    printf("Average waiting time of the processes is : %f\n",Avg_WT);
    printf("Average turn around time of the processes is : %f\n",Avg_TAT);
    return 0;
}

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