// Lab 4: Complex.java
// Definition of class Complex

public class Complex {
   private double real;
   private double imaginary;

   // Initialize both parts to 0
   /* Write header for a no-argument constructor. */
   { 
      /* Write code here that calls the Complex constructor that takes 2 
         arguments and initializes both parts to 0 */
   }

   // Initialize real part to r and imaginary part to i
   /* Write header for constructor that takes two arguments梤eal part r and
      imaginary part i. */
   {
      /* Write line of code that sets real part to r. */
      /* Write line of code that sets imaginary part to i. */
   }

   // Add two Complex numbers
   public Complex add( Complex right )
   {
      /* Write code here that returns a Complex number in which the real part is
         the sum of the real part of this Complex object and the real part of the
         Complex object passed to the method; and the imaginary part is the sum 
         of the imaginary part of this Complex object and the imaginary part of 
         the Complex object passed to the method. */
   }

   // Subtract two Complex numbers
   public Complex subtract( Complex right )
   {
      /* Write code here that returns a Complex number in which the real part is
         the difference between the real part of this Complex object and the real
         part of the Complex object passed to the method; and the imaginary part 
         is the difference between the imaginary part of this Complex object and
         the imaginary part of the Complex object passed to the method. */
   }

   // Return String representation of a Complex number
   public String toComplexString() 
   { 
      return "(" + real + ", " + imaginary + ")"; 
   }

} // end class Complex

// Lab 4: ComplexTest.java
// Test the Complex number class

import javax.swing.*;

public class ComplexTest {
   public static void main( String args[] )
   {
      Complex a, b;
      a = new Complex( 9.9, 7.7 );
      b = new Complex( 1.4, 3.1 );
 

      String result = "a = " + a.toComplexString();
      result += "\nb = " + b.toComplexString();
      result += "\na + b = " + a.add( b ).toComplexString();
      result += "\na - b = " + a.subtract( b ).toComplexString();
   

      JOptionPane.showMessageDialog( null, result, "Complex Test",
         JOptionPane.INFORMATION_MESSAGE );
      System.exit( 0 );
   }
}