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First Come First Serve (FCFS) Page replacement algorithm in C Programming

#include< stdio.h>
#include< conio.h>
int fsize;
int frm[15];
void display();
void main()
{
 int pg[100],nPage,i,j,pf=0,top=-1,temp,flag=0;
 clrscr();
 printf("\n Enter frame size:");
 scanf("%d",&fsize);
 printf("\n Enter number of pages:");
 scanf("%d",&nPage);

 for(i=0;i< nPage;i++)
 {
  printf("\n Enter page[%d]:",i+1);
  scanf("%d",&pg[i]);
 }
   for(i=0;i< fsize;i++)
    frm[i]=-1;
printf("\n page | \t Frame content ");
printf("\n--------------------------------------");
for(j=0;j< nPage;j++)
{
 flag=0;
  for(i=0;i< fsize;i++)
  {
   if(frm[i]==pg[j])
   {
    flag=1;
    break;
   }
  }


  if(flag==0)
  {
   if(top==fsize-1)
   {
    top=-1;
   }
   pf++;
   top++;
   frm[top]=pg[j];
  }
 printf("\n %d    |",pg[j]);
 display();
}
  printf("\n--------------------------------------");
 printf("\n total page fault:%d",pf);
getch();
}
void display()
{
 int i;
 for(i=0;i< fsize;i++)
  printf("\t %d",frm[i]);
}

OUTPUT
Enter frame size:3

 Enter number of pages:12

 Enter page[1]:1
 Enter page[2]:2
 Enter page[3]:3
 Enter page[4]:4
 Enter page[5]:1
 Enter page[6]:2
 Enter page[7]:5
 Enter page[8]:1
 Enter page[9]:2
 Enter page[10]:3
 Enter page[11]:4
 Enter page[12]:5

 page |          Frame content
--------------------------------------
 1    |  1       -1      -1
 2    |  1       2       -1
 3    |  1       2       3
 4    |  4       2       3
 1    |  4       1       3
 2    |  4       1       2
 5    |  5       1       2
 1    |  5       1       2
 2    |  5       1       2
 3    |  5       3       2
 4    |  5       3       4
 5    |  5       3       4
--------------------------------------
 total page fault:9

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