Write an OS program to implement C-LOOK algorithm Disk Scheduling algorithm.

 #include<stdio.h>

#include<stdlib.h>

int main()

{

    int initial_head_pos, direction, num_requests,temp,total_seek=0,current_head_pos,n=0;

    float avg_seek_time;

   

    printf("Enter initial head position : ");

    scanf("%d",&initial_head_pos);

   

    printf("Enter the direction (0 for left 1 for right) : ");

    scanf("%d",&direction);

   

    printf("Enter the number of disk requests : ");

    scanf("%d",&num_requests);

   

    int request_queue[num_requests];

   

    printf("Enter the disk queue : ");

    for (int i=0;i<num_requests;i++)

    {

         scanf("%d",&request_queue[i]);

    }    

    for (int i=0;i<num_requests-1;i++)

    {

         for (int j=0;j<num_requests-1;j++)

         {

              if (request_queue[j]>request_queue[j+1])

              {

                  temp = request_queue[j];

                  request_queue[j]=request_queue[j+1];

                  request_queue[j+1]=temp;

              }

         }

    }

   

    int i;

    for (i=0;i<num_requests;i++)

    {

         if (request_queue[i]>=initial_head_pos)

         {

             n=i;

             break;

         }

    }

   

    current_head_pos=initial_head_pos;

   

    if (direction==1)

    {

        printf("Initial Head Position : %d\n",current_head_pos);

        for (int j=i;j<num_requests;j++)

        {

             total_seek+=abs(request_queue[j]-current_head_pos);

             current_head_pos = request_queue[j];

             printf("Head Moving towards %d\n",current_head_pos);

        }

        current_head_pos = request_queue[0];

       

        for (int j=1;j<n;j++)

        {

             printf("Head Moving towards %d\n",current_head_pos);

             total_seek+=abs(request_queue[j]-current_head_pos);

             current_head_pos=request_queue[j];

             

        }

        printf("Head Moving towards %d\n",current_head_pos);

    }

    else

    {

        printf("Initial Head Position : %d\n",current_head_pos);

        for (int j=i-1;j>=0;j--)

        {

             printf("Head Moving towards %d\n",current_head_pos);

             total_seek+=abs(request_queue[j]-current_head_pos);

             current_head_pos=request_queue[j];

             

        }

        current_head_pos = request_queue[num_requests-1];

        for (int j=num_requests-1;j>=n;j--)

        {

             printf("Head Moving towards %d\n",current_head_pos);

             total_seek+=abs(request_queue[j]-current_head_pos);

             current_head_pos = request_queue[j];

             

        }

        printf("Head Moving towards %d\n",current_head_pos);

       

    }

    printf("Total seek movement : %d\n",total_seek);

   

    return 0;

}

/**

ty56@pc16:~/ty56/ty_OS2_56/Assignment 3$ cc clook.c

ty56@pc16:~/ty56/ty_OS2_56/Assignment 3$ ./a.out

Enter initial head position : 53

Enter the direction (0 for left 1 for right) : 0

Enter the number of disk requests : 7

Enter the disk queue : 82

170

43

140

24

16

190

Initial Head Position : 53

Head Moving towards 53

Head Moving towards 43

Head Moving towards 24

Head Moving towards 190

Head Moving towards 190

Head Moving towards 170

Head Moving towards 140

Head Moving towards 82

Total seek movement : 145

ty56@pc16:~/ty56/ty_OS2_56/Assignment 3$

ty56@pc16:~/ty56/ty_OS2_56/Assignment 3$ cc clook.c

ty56@pc16:~/ty56/ty_OS2_56/Assignment 3$ ./a.out

Enter initial head position : 53

Enter the direction (0 for left 1 for right) : 1

Enter the number of disk requests : 7

Enter the disk queue : 82

170

43

140

24

16

190

Initial Head Position : 53

Head Moving towards 82

Head Moving towards 140

Head Moving towards 170

Head Moving towards 190

Head Moving towards 16

Head Moving towards 24

Head Moving towards 43

Total seek movement : 164

**/