public class Line
{
   private static double EPSILON=1E-14;
   private double cx1;
   private double cy1;
   private double cx2;
   private double cy2;
   private double m;
   private double cb;
   private double ca;

   //When (x,y) and m are given
   public Line(double x1, double y1, double slope)
   {
      //Sets the variables
      cx1=x1;
      cy1=y1;
      m=slope;

      //Finds b for y=mx+b
      cb=(cx1*m)-y1;
   }

   //When (x1, y1) and (x2, y2) are given
   public Line(double x1, double y1, double x2, double y2)
   {
      //Sets the variables
      cx1=x1;
      cy1=y1;
      cx2=x2;
      cy2=y2;

      //Finds the slope
      m=(cy2-cy1)/(cx2-cx1);

      //Finds b for y=mx+b
      cb=(cx1*m)-y1;
   }

   //When y=mx+b is given
   public Line(double slope, double b)
   {
      //Sets the variables
      m=slope;
      cb=b;

   }

   //When x=a is given for vertical lines
   public Line(double a)
   {
      //Sets the variables
      ca=a;

      //Slope and y intercept are zero, since it's vertical
      m=0;
      cb=0;

   }


   public boolean intersects(Line other)
   {
      if(Math.abs(m-other.m) > EPSILON)
         return true;
      else
         return false;
   }

   public boolean equals(Line other)
   {
      if((Math.abs(m-other.m) < EPSILON) && (Math.abs(cb-other.cb) < EPSILON))
         return true;
      else
         return false;
   }

   public boolean isParallel(Line other)
   {
      if(Math.abs(m-other.m) < EPSILON)
         return true;
      else
         return false;
   }
}