//	Ex523.cc

//	Sec. 5.2 of lecture
//	structure in structure
//		a.out < input.523

#include <iostream.h>
#include <math.h>

main()
{
//			Define structures
 struct Point3D
  {
   double x,y,z;	// Coordinates
  };
 struct Line3D
  {
   Point3D p1,p2;	// Points
  };

//			Define variables
 Line3D line;
 double length;
//			Input data
 cout << endl;
 cout << "Input Line , Point 1 (x,y,z) : "; 
 cin  >> line.p1.x >> line.p1.y >> line.p1.z;
 cout << "             Point 2 (x,y,z) : "; 
 cin  >> line.p2.x >> line.p2.y >> line.p2.z;
 
 length = sqrt( (line.p2.x-line.p1.x)*(line.p2.x-line.p1.x) 
               +(line.p2.y-line.p1.y)*(line.p2.y-line.p1.y)
               +(line.p2.z-line.p1.z)*(line.p2.z-line.p1.z) );
 cout << endl;
 cout << " has length  " << length << endl;
 cout << endl;
 
}