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

void main()
{
  int 	gd, gm ;
  int 	x1 , y1 , x2 , y2 ;

  int 	wxmin , wymin , wxmax , wymax ;
  float u1 = 0.0  , u2 = 1.0 ;

  int  	p1 , q1 , p2 , q2 , p3 , q3 , p4 ,q4 ;
  float r1 , r2 , r3 , r4 ;
  int 	x11 , y11 , x22 , y22 ;

  clrscr();
  printf("Enter the windows left , bottom boundry\n");
  scanf("%d%d",&wxmin,&wymin);
  printf("Enter the windows right ,bottom boundry\n");
  scanf("%d%d",&wxmax,&wymax);

  printf("Enter line x1 , y1 co-ordinate\n");
  scanf("%d%d",&x1,&y1);

  printf("Enter line x2 , y2 co-ordinate\n");
  scanf("%d%d",&x2,&y2);


  p1 = -(x2 - x1 ); q1 = x1 - wxmin ;
  p2 = ( x2 - x1 ) ; q2 = wxmax - x1 ;
  p3 = - ( y2 - y1 ) ; q3 = y1 - wymin ;
  p4 = ( y2 - y1  ) ; q4 = wymax - y1 ;

  if( ( ( p1 == 0.0 ) && ( q1 < 0.0 ) ) ||
      ( ( p2 == 0.0 ) && ( q2 < 0.0 ) ) ||
      ( ( p3 == 0.0 ) && ( q3 < 0.0 ) ) ||
      ( ( p4 == 0.0 ) && ( q4 < 0.0 ) ) )
    {
	  printf("Line is rejected\n");
	  initgraph(&gd,&gm,"");
	  setcolor(2);
	  rectangle(wxmin,wymax,wxmax,wymin);
	  setcolor(1);
	  line(x1,y1,x2,y2);
	  getch();
	  setcolor(0);
	  line(x1,y1,x2,y2);
	  getch();
    }
 else
  {
  if( p1 != 0.0 )
	 {
		r1 =(float) q1 /p1 ;
		if( p1 < 0 )
		 u1 = max(r1 , u1 );
	    else
		 u2 = min(r1 , u2 );
	 }
 if( p2 != 0.0 )
	 {
	  r2 = (float ) q2 /p2 ;
	  if( p2 < 0 )
		 u1 = max(r2 , u1 );
	    else
		 u2 = min(r2 , u2 );

	 }
 if( p3 != 0.0 )
	 {
	  r3 = (float )q3 /p3 ;
	  if( p3 < 0 )
		 u1 = max(r3 , u1 );
	    else
		 u2 = min(r3 , u2 );
	 }
 if( p4 != 0.0 )
	 {
	   r4 = (float )q4 /p4 ;
	   if( p4 < 0 )
		 u1 = max(r4 , u1 );
	    else
		 u2 = min(r4 , u2 );
	 }

   if( u1 > u2 )
	printf("line rejected\n");
   else
    {
	  x11 = x1 + u1 * ( x2 - x1 ) ;
	  y11 = y1 + u1 * ( y2 - y1 ) ;

	  x22 = x1 + u2 * ( x2  - x1 );
	  y22 = y1 + u2 * ( y2 - y1 );

	printf("Original line cordinates\n");
	printf("x1 = %d , y1 =  %d, x2 =  %d, y2 =  %d\n",x1,y1,x2,y2);

	printf("Windows coordiante are \n");
	printf("wxmin = %d, wymin = %d,wxmax = %d , wymax = %d ",wxmin,wymin,wxmax,wymax);

	printf("New coordinates are \n");
	printf("x1 = %d, y1 = %d,x2 = %d , y2 = %d\n",x11,y11,x22,y22);

	initgraph(&gd,&gm,"");
	setcolor(2);
	rectangle(wxmin,wymax,wxmax,wymin);
	setcolor(1);
	line(x1,y1,x2,y2);
	getch();
	setcolor(0);
	line(x1,y1,x2,y2);

	setcolor(3);
	line(x11,y11,x22,y22);
	getch();

    }
 }
}
/*-*****************************************************************-*/