Scandisk.c

#include<stdio.h>      

int main()

{

 	int i,h,n,sum=0,d,t,j;	printf("Enter no.of request:");

	scanf("%d",&n);

	int r[n];

	printf("Enter request sequence:\n");

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

	{

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

	}   

	printf("Enter initial head position:");

	scanf("%d",&h);

	printf("Enter total disk size:");

	scanf("%d",&t);

	printf("Enter head movement direction(low:0,high:1):");

	scanf("%d",&d);

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

     {

        for(j=0;j<n-i-1;j++)

        {

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

            {

                int temp;

                temp=r[j];

                r[j]=r[j+1];

                r[j+1]=temp;

            }

        }

     }

   	if(d==0)

	{

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

		{

			if(h<=r[i])

			{

				j=i;

				break;

			}

		}  

		for(i=j-1;i>=0;i=i-1)

		{

			sum=sum+(h-r[i]);

			h=r[i];

			if(i==0)

			{

				sum=sum+h;

				h=0;	

			}

		}

		for(i=j;i<n;i++)

		{

			sum=sum+(r[i]-h);

			h=r[i];

		}

	}

	else

	{

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

		{

			if(h<=r[i])

			{

				j=i;

				break;

			}

		}  

		for(i=j;i<n;i++)

		{

			sum=sum+(r[i]-h);

			h=r[i];

			if(i==(n-1))

			{

				sum=sum+((t-1)-h);

				h=t-1;	

			}

		}

		for(i=j-1;i>=0;i=i-1)

		{

			sum=sum+(h-r[i]);

			h=r[i];

		}

	}

	printf("Total head movement:%d",sum);

	return 0;

}