Need help with creating an array that asked the user for the input with char. So
ID: 3638249 • Letter: N
Question
Need help with creating an array that asked the user for the input with char. So just the first half/quarter of the program.
The local Driver's License Office has asked you to write a program that grades the written portion of the driver's license exam. The exam has 20 multiple choice questions. Here are the correct answers:
1. B 6. A 11. B 16. C
2. D 7. B 12. C 17. C
3. A 8. A 13. D 18. B
4. A 9. C 14. A 19. D
5. C 10. D 15. D 20. A
A student must correctly answer 15 of the 20 questions to pass the exam.
Write a class named DriverExam that holds the correct answers to the exam in an array field. The class should also have an array field that holds the student's answers. The class should have the follow methods:
- passed. Returns true if the student passed the exam, or false if the student failed
- totalCorrect. Returns the total number of correctly answered questions
- totalIncorrect. Returns the total number of incorrectly answered questions
- questionsMissed, An int array containing the question numbers of the questions that the student missed
Demonstrate the class in a complete program that asks the user to enter a student's answers, and then displays the results returned from the DriverExam class's methods.
Input Validation: Only accept the letters A, B, C, or D as answers.
Explanation / Answer
{
private String[] correctAnswers = {"B","D","A","A","C","A","B","A","C","D", "B","C","D","A", "D","C","C","B","D","A"};
private String[] userAnswers;
int[] missed = new int[correctAnswers.length];
public DriverExam(String[] Answers)
{
userAnswers=new String[Answers.length];
for (int i = 0; i < Answers.length; i++)
{
userAnswers[i]=Answers[i];
}
}
public boolean passed()
{
if(totalCorrect() >= 15)
return true;
else
return false;
}
public int totalCorrect()
{
int correctCount=0;
for (int i = 0; i < correctAnswers.length; i++)
{
if (userAnswers[i].equalsIgnoreCase(correctAnswers[i]))
{
correctCount++;
}
}
return correctCount;
}
public int totalIncorrect()
{
int incorrectCount=0;
for (int i = 0; i < correctAnswers.length; i++)
{
if (!userAnswers[i].
equalsIgnoreCase(correctAnswers[i]))
{
missed[incorrectCount] = i;
incorrectCount++;
}
}
return incorrectCount;
}
public int[] questionsMissed()
{
return missed;
}
}
public class DriverExamApplication
{
public static void main(String[] args)
{
System.out.println(" Driver's License Exam ");
Scanner kb = new Scanner(System.in);
System.out.println(" 20 Multiple choice questions Mark A,B,C,D .");
String[] answers = new String[20];
String answer;
for (int i = 0; i < 20; i++)
{
do
{
System.out.print((i + 1) + ": ");
answer = kb.nextLine();
}while (!isValidAnswer(answer));
answers[i] = answer;
}
DriverExam exam = new DriverExam(answers);
System.out.println(" RESULTS ");
System.out.println("Total Correct: " + exam.totalCorrect());
System.out.println("Total Incorrect: " + exam.totalIncorrect());
String passed = exam.passed() ? "YES" : "NO";
System.out.println("Passed: " + passed);
if (exam.totalIncorrect() > 0)
{
System.out.println("The incorrect answers are:");
int missedIndex;
for (int i = 0; i < exam.totalIncorrect(); i++)
{
missedIndex = exam.questionsMissed()[i] + 1;
System.out.print(" " + missedIndex);
}
}
}
public static boolean isValidAnswer(String answer)
{
return "A".equalsIgnoreCase(answer) || "B".equalsIgnoreCase(answer)|| "C".equalsIgnoreCase(answer) || "D".equalsIgnoreCase(answer);
}