Disk Scheduling Algorithm (Complete)

#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<graphics.h>

main()
{
int gd=DETECT,gm,x,y,a1,x1,y1,a,b;
int req[30],head,i,k,move,n,ch,t1,t2,max,min,g[30],c,h;
initgraph(&gd,&gm,"z:\tcpp\bgi");
/*int req[30],head,i,k,move,n,ch,t1,t2,max,min,g[30],c,h;*/
clearviewport();
printf("(1) LOOK (2) CLOOK (3) FCFS (0) EXIT
Enter your choice:
");
scanf("%d",&ch);

while(ch)
{
printf("Enter the current head position: ");
scanf("%d",&head); h=head;
printf("Enter the number of requests: ");
scanf("%d",&n); k=0; move=0;
printf("Total number of cylinders: 200.
");
printf("Enter the requests (1 to 200):
");
req:
for(i=0;i<n;i++)
{
scanf("%d",&req[i]);
if(req[i]>200||req[i]<1)
{ printf("Enter requests only between 1-200."); goto req; }
}

switch(ch)
{
case 1:
outtextxy(270,10,"SEEK PATTERN FOR LOOK");
max=req[0]; min=req[0]; t2=1; c=0;
for(i=1;i<n;i++)
{
max=max>req[i]?max:req[i];
min=min<req[i]?min:req[i];
}
if(max<=head) t2=0;
while(k<n)
{
t1=0;
for(i=0;i<n;i++)
{
if(t2)
{
if(req[i]&&req[i]>=head)
{
if(req[i]<req[t1]) t1=i;
if(req[i]==max)
{ t2=0; g[c]=1; c++; }
}
}

else
{
if(req[i]&&req[i]<=head)
{
if(req[i]>req[t1]) t1=i;
if(req[i]==min)
{ t2=1; g[c]=200; c++; }
}
}
}/*for*/
printf("%d ",req[t1]);
g[c]=req[t1]; c++;
move+=abs(head-req[t1]);
req[t1]=0; k++;
head=req[t1];
if(head==max) t2=0;
}/*while*/
break;

case 2:
outtextxy(270,10,"SEEK PATTERN FOR CLOOK");
max=req[0]; min=req[0]; t2=1; c=0;
for(i=1;i<n;i++)
{
max=max>req[i]?max:req[i];
min=min<req[i]?min:req[i];
}
while(k<n)
{
t1=0;
if(!t2) head=min;
for(i=0;i<n;i++)
{
if(req[i]&&req[i]>=head)
{
if(req[i]<req[t1]) t1=i;
else if(req[i]==max)
{ head=1; g[c]=1; c++; }
}
}/*for*/
printf("%d ",req[t1]);
move+=abs(head-req[t1]);
head=req[t1];
g[c]=req[t1]; c++;
req[t1]=0; k++;
if(head==max) t2=0;
}/*while*/
break;

case 3:
outtextxy(270,10,"SEEK PATTERN FOR FCFS");
for(i=0,c=0;i<n;i++,c++)
{
printf("%d ",req[i]);
move+=abs(head-req[i]);
head=req[i];
g[c]=req[i];
}
break;
}/*switch*/
printf("Order of servicing:
");
printf("%d: ",h);
for(i=0;i<n;i++)
printf("%d ",g[i]);
printf("
Total Head Movements: %d
",move);
x=getmaxx();
y=getmaxy();
rectangle(0,20,x-5,y-5);

a1=(x-30)/10;

b=110; a=h+(3*a1); y1=125;
fillellipse(a,b,2,2);


for(i=0;i<n;i++)
{
int x1=g[i]+(3*a1);
fillellipse(x1,y1,2,2);
line(a,b,x1,y1);
a=x1; b=y1;
y1+=15;
}

getch();
clrscr(); clearviewport();
printf("
(1) LOOK (2) CLOOK (3) FCFS (0) EXIT
Enter your choice:
");
scanf("%d",&ch);
}/*while*/
getch();
}/*main*/

C-LOOK Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define max 20
#define cymax 199

int i,j,req,ttl_tracks=0,cp,np,cposn,nposn;
int cyposn[max],temp;

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
  scanf("%d",&cyposn[i]);
}

void CLOOK()
{
 for(i=0;i<=req;i++)
 {
  for(j=0;j<req-i;j++)
  {
   if(cyposn[j] > cyposn[j+1])
   {
    temp = cyposn[j];
    cyposn[j] = cyposn[j+1];
    cyposn[j+1] = temp;
   }
  }
 }
 cp=0;
 do
 {
  if(cyposn[cp] == cposn)
   break;
  cp++;
 }while(cp!=req);
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 i=0,j=cp;
 cposn = cyposn[cp];
 do
 {
  if(cp == req)
  { nposn = cyposn[0]; cp = 0; }
  else
   nposn = cyposn[++cp];
  printf(" %d\t\t%d\t\t%d\t\t%d\n",++i,cposn,nposn,abs(cposn-nposn));
  ttl_tracks += (abs(cposn-nposn));
  cposn = nposn == cyposn[req] ? cyposn[0] : nposn ;
 }while(nposn != cyposn[j-1]);
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
 CLOOK();
 getch();
}

FCFS Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define max 20
#define cymax 199

int i,req,ttl_tracks=0,cposn;
int cyposn[max];

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
  scanf("%d",&cyposn[i]);
}

void FCFS()
{
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 for(i=0;i<req;i++)
 {
  printf(" %d\t\t%d\t\t%d\t\t%d\n",i+1,cyposn[i],cyposn[i+1],abs(cyposn[i]-cyposn[i+1]));
  ttl_tracks += (abs(cyposn[i]-cyposn[i+1]));
 }
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
 FCFS();
 getch();
}

SSTF Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<limits.h>
#include<math.h>
#define max 20
#define cymax 199

int i,j,req,ttl_tracks=0,cp,np,cposn;
int cyposn[max],ind[max],temp;

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
 {
  scanf("%d",&cyposn[i]);
  ind[i] = 0;
 }

}

void search_short()
{
 int npl,npr,tmpr,tmpl;
 if(cp == 0)
 {
  np = cp;
  while(ind[np] == 1 && np < req)
   np++;
 }
 else if(cp == req)
 {
  np = cp;
  while(ind[np] == 1 && np > 0)
   np--;
 }
 else
 {
  npl = cp;
  while(ind[npl] == 1 && npl > 0)
   npl--;
  if(npl == 0 && ind[npl] == 1)
   tmpl = INT_MAX;
  else
   tmpl = cyposn[npl];
  npr = cp;
  while(ind[npr] == 1 && npr < req)
   npr++;
  if(npl == req && ind[npr] == 1)
   tmpr = INT_MAX;
  else
   tmpr = cyposn[npr];
  if(abs(cyposn[cp] - tmpl) < abs(cyposn[cp] - tmpr))
   np = npl;
  else
   np = npr;
 }
 ind[np] = 1;
}

void SSTF()
{
 for(i=0;i<=req;i++)
 {
  for(j=0;j<req-i;j++)
  {
   if(cyposn[j] > cyposn[j+1])
   {
    temp = cyposn[j];
    cyposn[j] = cyposn[j+1];
    cyposn[j+1] = temp;
   }
  }
 }
 cp=0;
 do
 {
  if(cyposn[cp] == cposn)
   break;
  cp++;
 }while(cp!=req);
 ind[cp] = 1;
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 i = 0 ;
 do
 {
  search_short();
  printf(" %d\t\t%d\t\t%d\t\t%d\t\t%d\n",i+1,cyposn[cp],cyposn[np],abs(cyposn[cp]-cyposn[np]),np);
  ttl_tracks += (abs(cyposn[cp]-cyposn[np]));
  cp = np;
  i++;
 }while(i!=req);
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
 SSTF();
 getch();
}

LOOK Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define max 20
#define cymax 199

int i,j,req,ttl_tracks=0,cp,np,cposn,nposn;
int cyposn[max],temp;

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
  scanf("%d",&cyposn[i]);
}

void LOOK()
{
 int ind = 0;
 for(i=0;i<=req;i++)
 {
  for(j=0;j<req-i;j++)
  {
   if(cyposn[j] > cyposn[j+1])
   {
    temp = cyposn[j];
    cyposn[j] = cyposn[j+1];
    cyposn[j+1] = temp;
   }
  }
 }
 cp=0;
 do
 {
  if(cyposn[cp] == cposn)
   break;
  cp++;
 }while(cp!=req);
 int tmp = cp;
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 i=0;
 cposn = cyposn[cp];
 do
 {
  if(ind == 0)
  {
   if(cp == 0)
   {
    cp = tmp;
    nposn = cyposn[++cp]; ind = 1;
   }
   else
    nposn = cyposn[--cp];
  }
  else
    nposn = cyposn[++cp];

  printf(" %d\t\t%d\t\t%d\t\t%d\n",++i,cposn,nposn,abs(cposn-nposn));
  ttl_tracks += (abs(cposn-nposn));
  cposn = nposn;
 }while(nposn!=cyposn[req]);
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
 LOOK();
 getch();
}

C-SCAN Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define max 20
#define cymax 199

int i,j,req,ttl_tracks=0,cp,np,cposn,nposn;
int cyposn[max],temp;

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
  scanf("%d",&cyposn[i]);
}

void CSCAN()
{
 for(i=0;i<=req;i++)
 {
  for(j=0;j<req-i;j++)
  {
   if(cyposn[j] > cyposn[j+1])
   {
    temp = cyposn[j];
    cyposn[j] = cyposn[j+1];
    cyposn[j+1] = temp;
   }
  }
 }
 cp=0;
 do
 {
  if(cyposn[cp] == cposn)
   break;
  cp++;
 }while(cp!=req);
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 i=0,j=cp;
 cposn = cyposn[cp];
 do
 {
  if(cposn == cyposn[req])
  { nposn = 199; cp = -1; }
  else
   nposn = cyposn[++cp];
  printf(" %d\t\t%d\t\t%d\t\t%d\n",++i,cposn,nposn,abs(cposn-nposn));
  ttl_tracks += (abs(cposn-nposn));
  cposn = nposn == 199 ? 0 : nposn;
 }while(nposn != cyposn[j-1]);
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
CSCAN();
 getch();
}

SCAN Disk Scheduling Algorithm

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define max 20
#define cymax 199

int i,j,req,ttl_tracks=0,cp,np,cposn,nposn;
int cyposn[max],temp;

void input()
{
 do
 {
  clreol();
  printf("\n Enter the current header position : ");
  scanf("%d",&cposn);
 }while(cposn>cymax || cposn <=0);
 printf("\n Enter the %d I/O Requests : ",req);
 cyposn[0] = cposn;
 for(i=1;i<=req;i++)
  scanf("%d",&cyposn[i]);



}

void SCAN()
{
 int ind = 0;
 for(i=0;i<=req;i++)
 {
  for(j=0;j<req-i;j++)
  {
   if(cyposn[j] > cyposn[j+1])
   {
    temp = cyposn[j];
    cyposn[j] = cyposn[j+1];
    cyposn[j+1] = temp;
   }
  }
 }
 cp=0;
 do
 {
  if(cyposn[cp] == cposn)
   break;
  cp++;
 }while(cp!=req);
 int tmp = cp;
 printf("\nS.No.  Current Position    Next Position   Displacement \n");
 printf("---------------------------------------------------------- \n\n");
 i=0;
 cposn = cyposn[cp];
 do
 {
  if(ind == 0)
  {
   if(cp == 0)
   { nposn = 0; ind = 1; }
   else
    nposn = cyposn[--cp];
  }
  else
  {
   if(cp == 0)
    cp = tmp;
   nposn = cyposn[++cp];
  }


  printf(" %d\t\t%d\t\t%d\t\t%d\n",++i,cposn,nposn,abs(cposn-nposn));
  ttl_tracks += (abs(cposn-nposn));
  cposn = nposn;
 }while(nposn!=cyposn[req]);
 printf("---------------------------------------------------------- \n\n");
 printf(" Total Tracks Displaced : %d",ttl_tracks);
}

void main()
{
 do
 {
  clrscr();
  printf("\n Enter the number of requests : ");
  scanf("%d",&req);
 }while(req>max || req <=0);
 input();
 SCAN();
 getch();
}