//Fifo Techinique of Paging

#include<iostream.h>
#include<graphics.h>
#include<stdlib.h>
#include<conio.h>

int seq,f,p,gd=DETECT,gm,q[20],front=0,rear=0,x=200,y=50,pgflt=0;
void draw(int ,int);
void insert(int);
void replace(int);
int doesntexist(int);
void draw();
void main()
{
	clrscr();
	initgraph(&gd,&gm,"E:\\Turboc\\bgi");
	cout<<"\t\t\t\tFIFO\n";
	cout<<"--------------------------------------------------------------\n\n";
	cout<<"Enter the no. of frames\n:";
	cin>>f;
	cout<<"Enter the no. of Pages\n:";
	cin>>p;
	cout<<"Enter the Sequence of Pages:\n";
	for(int i=0;i<p;i++)
		insert(i);
	cout<<"Total Pagefault = "<<pgflt;
	cout<<"\n\n\n\t\t\t..ANY KEY TO EXIT..";
	getch();
}
void insert(int i)
{
	if(rear-front==f)
	{
		cout<<"\n\nReplace\n\n";
		replace(i);
	}
	cin>>seq;
	if(doesntexist(seq)==1)
	{
		pgflt++;
		q[rear]=seq;
		rear=(rear+1)%f;
	}
	x=x+30;
	draw(x,y);
}
void replace(int v)
{
	if(front==rear)	cout<<"\n\nEmpty\n\n";
	else
	{
		q[front]=v;
		front=(front+1)%f;
	}
}
int doesntexist(int v)
{
	for(int i=0;i<f;i++)
		if(q[i]==v)
			return(0);
	return(1);
}
void draw(int x,int y)
{
	char *str;
	for(int j=0;j<f;j++)
	{
		rectangle(x,y+j*30,x+30,y+j*30+30);
		itoa(q[j],str,10);
		outtextxy((2*(x)+30)/2,(2*(y+j*30)+30)/2,str);
	}
}