'c' code for first come first serve page replacement algorithm.

#include<stdio.h>
#include<conio.h>
int main()
{
clrscr();
int i,j,n,a[50],frame[10],no,k,avail,count=0;
printf("\n ENTER THE NUMBER OF PAGES:\n");
scanf("%d",&n);
printf("\n ENTER THE PAGE NUMBER :\n");

for(i=1;i<=n;i++)
{
 scanf("%d",&a[i]);
}
printf("\n ENTER THE NUMBER OF FRAMES :");
scanf("%d",&no);
 for(i=0;i<no;i++)
  {
    frame[i]= -1;
  }
j=0;

for(i=0;i<n;i++)
  {

    avail=0;
    for(k=0;k<no;k++)
    {
      if(frame[k]==a[i])
      avail=1;
    }
if (avail==0)
 {
   frame[j]=a[i];
   j=(j+1)%no;
   count++;
 }
}
printf("Page Fault Is %d",count);

getch();
}