ANSWERS FOR MIDTERM C

1a.   x    y    x > 0   Output:
    ----+-----+------   3
     107   0    true
      21   1    true
       4   2    true
       0   3    false 

1b.  int y = 0;
     for(int x = 107; x > 0; x /= 5)
        y++;
     System.out.println(y);

1c.  Then there would be no body to the while top,
     the condition would never change and the
     while loop would be true and repeat forever.

2.  x     y         a    x + y > 0  x + y > 50
  -----+-----+----------+----------+----------
     2    7   abc          true       false
    13   34   34abc        true       false
    73  175   17334abc     false      true
              17534abc73   false      true

              Output:
              17534abc73   false      true

3. public static void main(String[] args)
   {
       double input;
       DecimalFormat df = new DecimalFormat("#0.00");
       input = Double.parseDouble(
           JOptionPane.showInputDialog("Enter amount in Francs."));
       System.out.println(input + " Francs gives you " +
           df.format(2.1 * output / 6.5) + " Marks.");
   }

    
3. public static void main(String[] args)
   {
       double hours, wage, totalWages = 0.0;
       DecimalFormat df = new DecimalFormat("#0.00");
       hours = Double.parseDouble(
           JOptionPane.showInputDialog("Enter hours."));
       wage = Double.parseDouble(
           JOptionPane.showInputDialog("Enter hours."));
       if (hours > 40)
           totalWages = 40.0 * wage + (40.0 - hours) * 1.5 * wage;
       else
           totalWages = wage * hours;
       System.out.println("Total wages are " + totalWages);
   }

4. public static void main(String[] args)
   {
       int number, maxEven = 0, maxOdd = 0;
       boolean existsAnEven = false, existsAnOdd = false;

       number = Integer.parseInt(
           JOptionPane.showInputDialog("Enter an int."));
       while(number >= 0)
       {
           if (number % 2 == 0)
	   {
               maxEven = Math.max(maxEven, number);
	       existsAnEven = true;
           }
           else
	   {
               maxOdd = Math.max(maxOdd, number);
	       existsAOdd = true;
           }
           number = Integer.parseInt(
              JOptionPane.showInputDialog("Enter an int."));
       }
       if (existsAnEven)
           System.out.println("The maximum even integer is " +
               maxEven + ".");
       else
           System.out.println("No even integers input.");

       if (existsAnOdd)
           System.out.println("The maximum odd integer is " +
               maxOdd + ".");
       else
           System.out.println("No odd integers input.");
   }

6. public void paint(Graphics g)
   {
       int i, x, y;

       for(i = 0; i <= 10000; i++)
       {
           x = (int) (50 * Math.random() + 50);
           y = (int) (50 * Math.random() + 50);
           g.fillOval(x, y, 1, 1);
           x = (int) (50 * Math.random() + 150);
           y = (int) (50 * Math.random() + 150);
           g.fillOval(x, y, 1, 1);
       }
   }