Bresenham line drwaing algorithm program in c

#include<stdio.h>
#include<graphics.h>
#include<math.h>

void lineBresen(float x1,float y1,float x2,float y2)
{
    int dx=abs(x2-x1),dy=abs(y2-y1),p,i=1;
    float x,y;
    if(x1<=x2)
    {
       x=x1;
       y=y1;
    }
    else
    {
       y=y2;
       x=x2;
    }
    p=((2*dy)-dx);
    putpixel(x,y,RED);
    while(i<=dx)
    {
      delay(100);
      x++;
      if(p<0)
      {
 p=p+(2*dy);
      }
      else
      {
 y++;
 p=p+(2*(dy-dx));
      }
      putpixel(x,y,RED);
     i++;
    }
}

int main()
{
   float x1,y1,x2,y2;
   int i,gd,gm;
   clrscr();

/* Initialise graphics mode
---------------------------------- */
detectgraph(&gd,&gm);
initgraph(&gd,&gm,"C://TurboC3//BGI");

/* Read two end points of line
---------------------------------- */
printf("Enter the value of x1 :\t");
scanf("%f",&x1);
printf("Enter the value of y1 :\t");
scanf("%f",&y1);
printf("Enter the value of x2 :\t");
scanf("%f",&x2);
printf("Enter the value of y2 :\t");
scanf("%f",&y2);
   lineBresen(x1,y1,x2,y2);

 getch();
 closegraph();
 return 0;
}