Optimal Page replacement algorithm in C Programming

#include< stdio.h>
#include< conio.h>
int fsize;
int frm[15];
void display();
void main()
{
 int pg[100],change[15],nPage,i,j,k,l,index,pf=0,temp,flag=0,flag1=0,found,max;
 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;
 flag1=0;
  for(i=0;i< fsize;i++)
  {
   if(frm[i]==pg[j])
   {
    flag=1;
    flag1=1;
    break;
   }
  }
  if(flag==0)
  {

   for(i=0;i< fsize;i++)
   {
    if(frm[i]==-1)
    {
     frm[i]=pg[j];
     pf++;
     flag1=1;
     break;
    }
   }
  }

  if(flag1==0)
  {
   for(i=0;i< fsize;i++)
    change[i]=0;


   for(i=0;i< fsize;i++)
   {
    for(k=j+1;l< =nPage;k++)
    {
     if(frm[i]==pg[k])
     {
      change[i]=k-j;
      break;
     }
    }
   }
   found=0;

   for(i=0;i< fsize;i++)
   {
    if(change[i]==0)
    {
     index=i;
     found=0;
     break;
    }
   }
   if(found==0)
   {
    max=change[0];
    index=0;

    for(i=1;i< fsize;i++)
    {
     if(max< change[i])
     {
      max=change
      [i];
      index=i;
     }
    }
   }
   frm[index]=pg[j];
   pf++;
  }
 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    |  1       2       4
 1    |  1       2       4
 2    |  1       2       4
 5    |  1       2       5
 1    |  1       2       5
 2    |  1       2       5
 3    |  3       2       5
 4    |  4       2       5
 5    |  4       2       5
--------------------------------------
 total page fault:7