class P1
{
    public static void main (String args [])
    {
        int arr[] []  = { {24, 0, 19}, {21, 6, -5},
                          {10, 16, 3}, {1, -1, 0} };
  
        for(int j = 0; j < arr[0].length; j++)
            for(int k = 0; k < arr.length - 1; k++)
                System.out.println( arr[k][j] );
    }
}

import javax.swing.*;
import java.awt.*;

public class Prob2 extends JFrame
{
    public static void main(String [] args)
    {
        Prob2 c1 = new Prob2();
    }

    Prob2()
    {
        JPanel p = new JPanel();
        Container c = getContentPane();
        p.setBackground(Color.pink);
        p.add(new JButton("One"));
        p.add(new JTextField("Two"));
        p.add(new JButton("Three"));
        c.add(p, "Center");
        c.setLayout(new FlowLayout());
        setSize(300, 300);
        setVisible(true);
    }
}

class P3
{   
    public static void main (String [] args)
    {
        A b = new B();
        b.whoAmI();
    }
}
 
class A
{
    public void whoAmI()
    {
        System.out.println("I'm an A object!");
    }
}
 
class B extends A
{
    public void whoAmI()
    {
        System.out.println("I'm a B object!");
    }
}

     ArrayList<int> numbers = new ArrayList<int>();
     numbers.add(7);
     numbers.add(19);
     System.out.println( numbers );	 	 	 

# E50b Final Exam, Spring 2001
# Decodes a message

        .text
main:             # SPIM starts by jumping to main.
                  # First read in string from the keyboard
        la     $a0,  string_space
        li     $a1, 1024
        li     $v0,  8  # load "read_string" code into $v0
        syscall
        
        la     $a0, string_space        
        jal    decode
        la     $a0, string_space
        li     $v0, 4
        syscall
        li     $v0, 10
        syscall
        
decode:   # Here is the subroutine!
        subu   $sp, $SP, 8
        sw     $ra, 4($SP) 
        SW     $fp, 
        addu   $FP, $SP, 8
        
loop:   lb     $t3, ($a0)
        beqz   $t3, exit
        blt    $t3, 'a', incr
        bgt    $t3, 'z', incr

 
   // Fill in the missing statements right here!
 
   ##( Part A )

 

 

 
incr:   sb     $t3, ($a0)        
        addu   $a0, $a0, 1
        b      loop
exit:   
   // Fill in more missing statements right here!
 
   ## ( Part B )

 

 

 

 
## Here's where the data for this program is stored:
        .data
string_space:    .space   1024

   subu   $t3, $t3, 3    # subtract the 3 places
   bge    $t3, 'a', incr # if the letter is still greater than or 
                         # equal to 'a', go to incr; we don't need
                         # to correct for the last three letters.
   addu   $t3, $t3, 26   # The letter was less than 'a', so we need
                         # to correct it, then go on to incr.

   lw     $ra, 4($sp)    # restore the return address
   lw     $fp, 0($sp)    # restore the frame pointer
   addu   $sp, $sp, 8    # move the stack pointer down
   jr     $ra            # go back to the instruction that
                         # called the subroutine

public class Prob10
{
    public static void main (String [] args)
    {
        Prob10Frame f = new Prob10Frame("Prob10", 300, 300);
    }
} 

When this program is executed, the following appears: a JFrame containing a JButton at the top and a JButton at the bottom.

The center space has been reserved for the user to draw small circles and squares simply by clicking the mouse inside a JPanel. The user can toggle between drawing circles versus squares by first clicking on one or the other JButton. Here's what the screen is supposed to look like after doing a bit of clicking:

Each circle or square is 20 pixels wide and 20 pixels high. The upper left-hand corner of each circle or square appears where I clicked the mouse. A somewhat incomplete version of this program is shown below. Your task is to fill in the missing code for the constructor

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class Prob10Frame extends JFrame

   JButton circleButton = new JButton("Press to draw CIRCLE!");
   JButton squareButton = new JButton("Press to draw SQUARE!");
   MyPanel mp = new MyPanel();
   boolean circleOrSquare = false;
   int xValue, yValue;
  
   public Prob10Frame(String name, int height, int width)
   {
       setTitle(name);
       setSize(height, width);
       setLocation(200, 200);

       Container c = getContentPane();
       ButtonListener bl = new ButtonListener();
       circleButton.addActionListener(bl);
       squareButton.addActionListener(bl);
          
       c.add(mp, BorderLayout.CENTER);
       c.add(squareButton, BorderLayout.SOUTH);
       c.add(circleButton, BorderLayout.NORTH);
       setVisible(true);
    }

    class MyPanel extends JPanel implements MouseListener
    {
        public MyPanel()
        {
           // missing code goes here!  Part (A).
        }

        public void mouseClicked(MouseEvent me)
        {
           Graphics g = getGraphics();
           xValue = me.getX();
           yValue = me.getY();
           if(circleOrSquare){
              g.fillRect(xValue, yValue, 20, 20);
           }
           else{
              g.fillOval(xValue, yValue, 20, 20);
           }
        }

        public void mouseReleased(MouseEvent me)
        { }

        public void mousePressed(MouseEvent me)
        { }

        public void mouseEntered(MouseEvent me)
        { }

        public void mouseExited(MouseEvent me)
        { }
    }

    class ButtonListener implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
           // missing code goes here!    Part (B).
        }
    }
}

        public MyPanel()
        {
            addMouseListener(this);
        }

        public void actionPerformed(ActionEvent e)
        {
            if(e.getSource() == squareButton){
                circleOrSquare = true;
            }
            else{                 // must be the circleButton
                circleOrSquare = false;
            }
        }