// Examples of some methods with void return type, or with no parameters

import java.util.Scanner;

public class Voids
{
  public static Scanner input = new Scanner(System.in);

  public static void main(String[] args)
  {
     char result;
     result = getALetter();	// no parameters, but returns a char

     printQuotient(9, 5);		// void function.  call by itself
     printQuotient(5, 0);

     System.out.println("Before killSomeTime() is called");
     killSomeTime();
     System.out.println("After killSomeTime() is called");
  }

  public static char getALetter()
  {
    boolean isLetter;
    char let;
    do
    {
      System.out.print("Please enter a letter of the alphabet: ");
      let = input.next().charAt(0);
      isLetter = (let >= 'A' && let <= 'Z') || (let >= 'a' && let <= 'z');

      if (!isLetter)
 	  System.out.println("Not a letter.  Try again.\n");

    } while (!isLetter);

    return let;
  }


  public static void printQuotient(int x, int y)
  {
     if (y == 0)
     {
        System.out.println("I'm not going to divide by 0 !");
        return;
     } 

     System.out.println("The quotient of " + x 
                      + " divided by " + y + " is: " + (x / y) );
  }

  public static void killSomeTime()
  // this function is going to just delay a little
  {
     long x = 0, y;
     while (x < 5000000000L)	// note: the L on this literal ensures
     {				//  it will be interpreted as type long
        y = x * x;
        x++;
     }
  }

}