CPU_schueduling_algorithms.c

#include<stdio.h>
int main(){
int ch;
do{
printf("\n1.FCFS\n2.SJF\n3.PIORITY\n4.ROUND ROBIN");
printf("\nEnter the choice :");
scanf("%d",&ch);

if(ch==1)
{
int bt[20],p[20],wt[20],tat[20],i,j,n,total=0,pos,temp,at[20];
    float avg_wt,avg_tat;
    printf("Enter number of process:");
    scanf("%d",&n);
  
    printf("\nEnter Burst Time:\n");
    for(i=0;i<n;i++)
    {
        printf("p%d:",i+1);
        scanf("%d",&bt[i]);
        p[i]=i+1;         
    }
printf("\nEnter arrival time:\n");
    for(i=0;i<n;i++)
    {
        printf("p%d:",i+1);
        scanf("%d",&at[i]);
        p[i]=i+1;         
    }
  
    for(i=0;i<n;i++)
    {
        pos=i;
        for(j=i+1;j<n;j++)
        {
            if(at[j]<at[pos])
                pos=j;
        }
  
        
        temp=bt[i];
        bt[i]=bt[pos];
        bt[pos]=temp;

	temp=at[i];
        at[i]=at[pos];
        at[pos]=temp;
        temp=p[i];
        p[i]=p[pos];
        p[pos]=temp;
    }
   
    wt[0]=0;            
  
   
    for(i=1;i<n;i++)
    {
        wt[i]=0;
        for(j=0;j<i;j++)
            wt[i]+=bt[j];
  
        total+=wt[i];
    }
  
    avg_wt=(float)total/n;      
    total=0;
  
    printf("\nProcess\t  arrival time \t  Burst Time    \tWaiting Time\tTurnaround Time");
    for(i=0;i<n;i++)
    {
        tat[i]=bt[i]+wt[i];   
        total+=tat[i];
        printf("\np%d\t\t %d\t\t %d\t\t    %d\t\t\t%d",p[i],at[i],bt[i],wt[i],tat[i]);
    }
  
    avg_tat=(float)total/n;    
    printf("\n\nAverage Waiting Time=%f",avg_wt);
    printf("\nAverage Turnaround Time=%f\n",avg_tat);
}
if(ch==2){


    int bt[20],p[20],wt[20],tat[20],i,j,n,total=0,pos,temp;
    float avg_wt,avg_tat;
    printf("Enter number of process:");
    scanf("%d",&n);
  
    printf("\nEnter Burst Time:\n");
    for(i=0;i<n;i++)
    {
        printf("p%d:",i+1);
        scanf("%d",&bt[i]);
        p[i]=i+1;         
    }
  
    for(i=0;i<n;i++)
    {
        pos=i;
        for(j=i+1;j<n;j++)
        {
            if(bt[j]<bt[pos])
                pos=j;
        }
  
        temp=bt[i];
        bt[i]=bt[pos];
        bt[pos]=temp;
  
        temp=p[i];
        p[i]=p[pos];
        p[pos]=temp;
    }
   
    wt[0]=0;            
  
   
    for(i=1;i<n;i++)
    {
        wt[i]=0;
        for(j=0;j<i;j++)
            wt[i]+=bt[j];
  
        total+=wt[i];
    }
  
    avg_wt=(float)total/n;      
    total=0;
  
    printf("\nProcess\t    Burst Time    \tWaiting Time\tTurnaround Time");
    for(i=0;i<n;i++)
    {
        tat[i]=bt[i]+wt[i];   
        total+=tat[i];
        printf("\np%d\t\t  %d\t\t    %d\t\t\t%d",p[i],bt[i],wt[i],tat[i]);
    }
  
    avg_tat=(float)total/n;    
    printf("\n\nAverage Waiting Time=%f",avg_wt);
    printf("\nAverage Turnaround Time=%f\n",avg_tat);
}
if(ch==3){
int bt[20],p[20],wt[20],tat[20],i,j,n,total=0,pos,temp,pt[20];
    float avg_wt,avg_tat;
    printf("Enter number of process:");
    scanf("%d",&n);
  
    printf("\nEnter Burst Time:\n");
    for(i=0;i<n;i++)
    {
        printf("p%d:",i+1);
        scanf("%d",&bt[i]);
        p[i]=i+1;         
    }
printf("\nEnter priority:\n");
    for(i=0;i<n;i++)
    {
        printf("p%d:",i+1);
        scanf("%d",&pt[i]);
        p[i]=i+1;         
    }
  
    for(i=0;i<n;i++)
    {
        pos=i;
        for(j=i+1;j<n;j++)
        {
            if(pt[j]<pt[pos])
                pos=j;
        }
  
        temp=pt[i];
        pt[i]=pt[pos];
        pt[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;            
  
   
    for(i=1;i<n;i++)
    {
        wt[i]=0;
        for(j=0;j<i;j++)
            wt[i]+=bt[j];
  
        total+=wt[i];
    }
  
    avg_wt=(float)total/n;      
    total=0;
  
    printf("\nProcess\t  priority \t  Burst Time    \tWaiting Time\tTurnaround Time");
    for(i=0;i<n;i++)
    {
        tat[i]=bt[i]+wt[i];   
        total+=tat[i];
        printf("\np%d\t\t %d\t\t %d\t\t    %d\t\t\t%d",p[i],pt[i],bt[i],wt[i],tat[i]);
    }
  
    avg_tat=(float)total/n;    
    printf("\n\nAverage Waiting Time=%f",avg_wt);
    printf("\nAverage Turnaround Time=%f\n",avg_tat);
}
if(ch==4)
{
      int i, limit, total = 0, x, counter = 0, time_quantum;
      int wait_time = 0, turnaround_time = 0, arrival_time[10], burst_time[10], temp[10];
      float average_wait_time, average_turnaround_time;
      printf("\nEnter Total Number of Processes:\t");
      scanf("%d", &limit);
      x = limit;
      for(i = 0; i < limit; i++)
      {
            printf("\nEnter Details of Process[%d]\n", i + 1);
 
            printf("Arrival Time:\t");
 
            scanf("%d", &arrival_time[i]);
 
            printf("Burst Time:\t");
 
            scanf("%d", &burst_time[i]);
 
            temp[i] = burst_time[i];
      }
 
      printf("\nEnter Time Quantum:\t");
      scanf("%d", &time_quantum);
      printf("\nProcess ID\t\tBurst Time\t Turnaround Time\t Waiting Time\n");
      for(total = 0, i = 0; x != 0;)
      {
            if(temp[i] <= time_quantum && temp[i] > 0)
            {
                  total = total + temp[i];
                  temp[i] = 0;
                  counter = 1;
            }
            else if(temp[i] > 0)
            {
                  temp[i] = temp[i] - time_quantum;
                  total = total + time_quantum;
            }
            if(temp[i] == 0 && counter == 1)
            {
                  x--;
                  printf("\nProcess[%d]\t\t%d\t\t %d\t\t\t %d", i + 1, burst_time[i], total - arrival_time[i], total - arrival_time[i] - burst_time[i]);
                  wait_time = wait_time + total - arrival_time[i] - burst_time[i];
                  turnaround_time = turnaround_time + total - arrival_time[i];
                  counter = 0;
            }
            if(i == limit - 1)
            {
                  i = 0;
            }
            else if(arrival_time[i + 1] <= total)
            {
                  i++;
            }
            else
            {
                  i = 0;
            }
      }
 
      average_wait_time = wait_time * 1.0 / limit;
      average_turnaround_time = turnaround_time * 1.0 / limit;
      printf("\n\nAverage Waiting Time:\t%f", average_wait_time);
      printf("\nAvg Turnaround Time:\t%f\n", average_turnaround_time);
      
}
}while(ch<=4);
}