tutorial pengulangan loop (J2SE)

import javax.swing.JOptionPane;
public class tutorialpengulanganloop{
    public static void main(String[]args){
int option=0;
while(option==JOptionPane.YES_OPTION){

int correctCount = 0;
int count = 0; // Count the number of questions
long startTime = System.currentTimeMillis();
String output = "";
while (count < 10) {
// 1. Generate two random single-digit integers
int number1 = (int)(Math.random() * 10);
int number2 = (int)(Math.random() * 10);

// 2. If number1 < number2, swap number1 with number2
if (number1 <number2){
int temp = number1;
number1 = number2;
number2 = temp;
}

// 3. Prompt the student to answer "what is number1 number2?"
String answerString = JOptionPane.showInputDialog
("What is " + number1 + " - " + number2 + "?");
int answer = Integer.parseInt(answerString);

// 4. Grade the answer and display the result
String replyString;
if (number1 - number2 == answer){
replyString = "You are correct !";
correctCount++;
}
else
replyString = "You answer is wrong.\n" + number1 + " - "
+ number2 + " should be " + (number1 - number2);
JOptionPane.showMessageDialog(null, replyString);

// Increase the count
count++;
output += "\n" + number1 + "-" + number2 + "=" + answerString +
((number1 - number2 == answer) ? "correct" : "wrong");
}

long endTime = System.currentTimeMillis();
long testTime = endTime - startTime;

JOptionPane.showMessageDialog(null,
"Correct count is " + correctCount + "\nTest time is " +
testTime / 1000 + " seconds\n" + output);

System.out.println("continue loop");
option = JOptionPane.showConfirmDialog(null, "continue?");

}
}
}