Program for Priority Scheduling

C++ Program for Priority Scheduling  (Non Preemptive)

#include<iostream>

using namespace std;

int main()

{

    int bt[20],p[20],wt[20],tat[20],pr[20],i,j,n,total=0,pos,temp,avg_wt,avg_tat;

    cout<<"Enter Total Number of Process:";

    cin>>n;

    cout<<"\nEnter Burst Time and Priority\n";

    for(i=0;i<n;i++)

    {

        cout<<"\nP["<<i+1<<"]\n";

        cout<<"Burst Time:";

        cin>>bt[i];

        cout<<"Priority:";

        cin>>pr[i];

        p[i]=i+1;           //contains process number

    }

    //sorting burst time, priority and process number in ascending order using selection sort

    for(i=0;i<n;i++)

    {

        pos=i;

        for(j=i+1;j<n;j++)

        {

            if(pr[j]<pr[pos])

                pos=j;

        }

        temp=pr[i];

        pr[i]=pr[pos];

        pr[pos]=temp;

        temp=bt[i];

        bt[i]=bt[pos];

        bt[pos]=temp;

        temp=p[i];

        p[i]=p[pos];

        p[pos]=temp;

    }

    wt[0]=0;            //waiting time for first process is zero

    //calculate waiting time

    for(i=1;i<n;i++)

    {

        wt[i]=0;

        for(j=0;j<i;j++)

            wt[i]+=bt[j];

        total+=wt[i];

    }

    avg_wt=total/n;      //average waiting time

    total=0;

    cout<<"\nProcess\t    Burst Time    \tWaiting Time\tTurnaround Time";

    for(i=0;i<n;i++)

    {

        tat[i]=bt[i]+wt[i];     //calculate turnaround time

        total+=tat[i];

        cout<<"\nP["<<p[i]<<"]\t\t  "<<bt[i]<<"\t\t    "<<wt[i]<<"\t\t\t"<<tat[i];

    }

    avg_tat=total/n;     //average turnaround time

    cout<<"\n\nAverage Waiting Time="<<avg_wt;

    cout<<"\nAverage Turnaround Time="<<avg_tat;

    return 0;

}

 
OUTPUT :

Program output for Priority Scheduling