11. AQuiz IAnswers

Interface: IAnswers

The IAnswers interface has the methods:

int numAnswers();
int getAnswer(int k);

Class: MCAnswers

The multiple choice answers class MCAnswers implements the IAnswers interface. Its constructor is:

public MCAnswers (int[] answers)

Abstract class: AQuiz

• Constructor takes in an IAnswers key of correct answers.
• method int score(IAnswers student) gives the score for the remembered student answer sheet.
• abstract method int scoreOne(int correct, int given) returns the score for a single answer.

Class: MCQuiz

• Subclass of AQuiz
• Constructor takes in a IAnswers key of correct answers.
• Scoring in the scoreOne method is 4 points for a correct answer and -1 point for a wrong answer.

Example

    int[] ans = {2,2,1,3,4};
    int[] student = {2,2,4,3,4};
    IAnswers a = new MCAnswers(ans);
    IAnswers s = new MCAnswers(student);       
    AQuiz b = new MCQuiz(a);
    int result = b.score(s);
    System.out.println(result); // prints 15 = +4 +4 -1 +4 +4