Operating_System/sjf.cpp at main · RezoneTahan/Operating_System · GitHub

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#include<iostream>
using namespace std;
int main()
{
    int n,temp,tt=0,min,d,i,j;
    float avg_tat=0,avg_wt=0,t_tat=0,t_wt=0;
    cout<<"Enter number of processes: ";
    cin>>n;
    int p[n], a[n] ,b[n] ,c[n] ,tat[n] , wt[n];
    cout<< "\nEnter process sequence:";
    for(i=0;i<n; i++)
    {

        cin>> p[i];

    }

    cout<< "\nEnter  the arrival times :\n";
    for(i=0;i<n; i++)
    {

        cin>> a[i];

    }

    cout<< "Enter  the CPU times :\n";
    for(i=0; i<n; i++)
    {

        cin>> b[i];

    }


    for(i=0;i<n;i++)
    {

        for(j=i+1;j<n;j++)
        {
            if(b[i]>b[j])

            {

                temp=p[i];
                p[i]=p[j];
                p[j]=temp;


                temp=a[i];
                a[i]=a[j];
                a[j]=temp;


                temp=b[i];
                b[i]=b[j];
                b[j]=temp;
            }
        }
    }

    min=a[0];
    for(i=0;i<n;i++)
    {


        if(min>a[i])
        {

            min=a[i];
            d=i;
        }


    }

      tt=min;
      c[d]=tt+b[d];
      tt=c[d];


      for(i=0;i<n;i++)
       {
           if(a[i]!=min)
           {
               c[i]=b[i]+tt;
               tt=c[i];
           }
       }


       for(i=0;i<n;i++)
       {
            tat[i]=c[i]-a[i];
            t_tat=t_tat+tat[i];
            wt[i]=tat[i]-b[i];
            t_wt +=wt[i];

            cout<<"\nProcess : "<<p[i]<<"  Waiting time : " << wt[i]<<" Turnaround Time: "<<tat[i]<<endl;

       }
       avg_tat=t_tat/n;
       avg_wt=t_wt/n;


       cout<< "\nAverage Turnaround Time: "<<avg_tat<<endl;
       cout<<"\nAverage Waiting Time: "<<avg_wt<<endl;

       return 0;
}