DDA line drawing algorithm program in c

/* DDA program
created by: Pirate */

#include<stdio.h>

#include<conio.h>

#include<graphics.h>

#include<math.h>

#include<dos.h>

void dda_line(int x1,int y1,int x2,int y2);

void main()

{

            int x1,y1,x2,y2,gd=DETECT,mode;

            clrscr();

            initgraph(&amp;gd,&amp;mode,"c:\\turboc3\\bgi");

            printf("Enter the starting point of line\n");

            scanf("%d %d",&amp;x1,&amp;y1);

            printf("\nEnter the ending point of line\n");

            scanf("%d %d",&amp;x2,&amp;y2);

            dda_line(x1,y1,x2,y2);

            getch();

}

void dda_line(int x1,int y1,int x2,int y2)

{

            float x,y,xinc,yinc,dx,dy;

            int k,length;

            dx=x2-x1;

            dy=y2-y1;

            if(abs(dx)&gt;abs(dy))

            length=abs(dx);

            else

            length=abs(dy);

            xinc=dx/length;

            yinc=dy/length;

            x=x1;

            y=y1;

            putpixel(x,y,7);

            for(k=1;k

            {

                        x=x+xinc;

                        y=y+yinc;

                        delay(10);

                        putpixel(x,y,7);

            }

}

Output