class Grades2 {
      public static void main (String args[]) {	
	final double MIDTERM_PERCENTAGE = .25;
  	final double FINALEXAM_PERCENTAGE = .25 ;
	final double RESEARCH_PERCENTAGE = .30 ;
	final double PRESENTATION_PERCENTAGE = .20 ;
	final double MATH_MIDTERM_PERCENTAGE= .50;
	final double MATH_FINALEXAM_PERCENTAGE =.50; 
	final double SCIENCE_MIDTERM_PERCENTAGE = .40 ;
	final double SCIENCE_FINALEXAM_PERCENTAGE = .40;
	final double SCIENCE_RESEARCH_PERCENTAGE = .20;
	int midterm = 0;
	int finaExamGrade= 0;
	int research = 0;
	int presentation = 0;
	double finalNumericGrade = 0; 
	String finalLetterGrade= "";
 String response ;
 // What type of student are we calculating?
response = JOptionPane.showInputDialog ("Enter student type 

1= English, 2= Math, 3 = Science") ;
if (response = null) {
System.exit (0);
}
while (response.equals("")) {
JOptionPane.showMessageDialog( null, "You must enter a 

number");
response = JOptionPane.showInputDialog("Enter student type 

1= English, 2= Math, 3= Science");
}
while (Integer.parseInt(response) < 1 | Integer.parseInt(

response) > 3) 
{
JOptionPane.showMessageDialog(null, response + " - is not a 

valid student type") ;
response = JOptionPane.showInputDialog("Enter student type 

1= English, 2= Math, 3= Science") ;
}
//Student type is valid, now let's calculate the grade
switch(Integer.parseInt(response)) {
// Case 1 is an English student
case 1 :
midterm = Integer.parseInt(JOptionPane.showInputDialog ("

Enter the Midterm Grade"));
finalExamGrade = Integer.parseInt(JOptionPane.

showInputDialog ("Enter the Final Exam Grade"));
research = Integer.parseInt(JOptionPane.showInputDialog("

Enter the research grade"));
presentation= Integer.parseInt(JOptionPane.showInputDialog

("Enter the presentation grade"));
finalNumericGrade= 
	(midterm * ENGLISH_MIDTERM_PERCENTAGE) +
	(finalExamGrade * ENGLISH_FINALEXAM_PERCENTAGE)+
	(research * ENGLISH_RESEARCH_PERCENTAGE) +
	(presentation * ENGLISH_PRESENTATION_PERCENTAGE) ;
if (finalNumericGrade >= 93) 
	finalLetterGrade= "A" ;
else
	if((finalNumericGrade >= 85) & (finalNumericGrade < 

93)) 
	finalLetterGrade = "B" ;
	
	else
	if ((finalNumericGrade >= 78) & (finalNumericGrade < 

85)) 
	finalLetterGrade = "C" ;
	
	else
	if ((finalNumericGrade >= 70) & (finalNumericGrade < 

78))
	finalLetterGrade = "D" ;
	
	else
	finalLetterGrade= "F" ;
JOptionPane.showMessageDialog(null, "***ENGLUSH STUD3NT*** 

\n\n" +
	"Midterm grade is: " + midterm + "\n" +
	"Final exam grade is: " + finalExamGrade + "\n" +
	"Research grade is: " + research + "\n" +
	"Presentation grade is: " + presentation + "\n\n" +
	"Final Numeric Grade is: " + finalNumericGrade + "

\n" +
	"Final Letter Grade is: " + finalLetterGrade) ;
break;
//Case 2 is a math student
case 2:
midterm = Integer.parseInt(JOptionPane.showInputDialog("

Enter teh midterm grade" ));
finalExamGrade= Integer.parseInt(JOptionPane.

showInputDialog("Enteer teh final xam grade"));
finalNumericGrade=
	(midterm * MATH_MIDTERM_PERCENTAGE) +
	(finalExamGrade * MATH_FINALEXAM_PERCENTAGE) ;
if (finalNumericGrade >= 90)
	finalLetterGrade= "A" ;
else
if ((finalNumericGrade >= 83) & (finalNumericGrade > 90)) 
	finalLetterGrade = "B" ;
else
if	(( finalNumericGrade >= 76) & (finalNumericGrade < 

83))
	finalLetterGrade= "C" ;
else
if (( finalNumericGrade >= 65) & (finalNumericGrade < 76)) 
	finalLetterGrade = "D" ;
else
if	(finalNumericGrade < 65)
	finalLetterGrade = "F" ;
	
JOptionPane.showMessageDialog (null, "*** MATH STUDENT *** 

\n\n" +
	"midterm grade is : " + midterm + "\n" +
	"Final exam grade is : " + finalExamGrade + "\n" +
	"Final numeric grade is : " + finalNumericGrade + "

\n" +
	"Final letter grade is : " + finalLetterGrade) ;
break;

case 3:
	midterm = Integer.parseInt(JOptionPane.

showInputDialog
	("Enter the midterm grade")); 
	finalExamGrade = Integer.parseInt(JOptionPane.

showInputDialog 
	("Enter the final exam grade")) ;
	research = Integer.parseInt(JOptionPane.

showInputDialog("Enter the research grade")) ;

	finalNumericGrade = JOptionsPane.showMessageDialog 

(null, "*** SCIENCE STUDENT *** \n\n " +
	"midterm grade is : " + midterm + "\n" +
	"final exam grade is :" + finalExamGrade + "\n" +
	"research grade is :" + research + "\n\n" +
	"final numeric grade is : "  + finalNumericGrade + 

"\n" +
	"final letter grade is : " + finalLetterGrade ); 
break; 
default :
	JOptionPane.showMessageDialog(null, response + " - 

is not a valid response");
	System.exit (0);
}

System.exit (0);

}
}