Prac 4 Question 6

import javax.swing.JOptionPane;

public class GradesQ6 {
public static void main(String[] args) {
double grade, sum = 0;
String inputStr;

int numModules = 0; // number of modules entered so far

//(a) Read and validate user grades as shown in Fig 5.1 to 5.3
do {
inputStr = JOptionPane.showInputDialog(null,
"Enter your marks for Module " + (numModules+1));
grade = Double.parseDouble(inputStr);

if (grade < 0) {
JOptionPane.showMessageDialog(null, "Input cannot be negative");
} else if (grade > 100) {
JOptionPane.showMessageDialog(null, "Input cannot be above 100");
}else{//valid input
numModules++;
sum+=grade;
}
} while (grade < 0 || grade > 100 || numModules<2);

//(c) Compute and display the results as shown in Fig 5.4
JOptionPane.showMessageDialog(null, "Average is " + sum / 2);

} //end main
} //end class