Pls help me - how to draw out questions wrongly answered from a pool of array

[Kareng]

Hi, I'm desparately trying to know how to do the code whereby I can dispaly the wrong questions answered from category chosen. There are 4 categories with 5 questions each and I need to dispaly all the wrong questions. So far my code only show the question 1 all the time.:confused:

import javax.swing.*;

public class Quiz {//Quiz Class

    public final static int NOOFQUESTION = 5;
    public final static int POOLSIZE = 20;
    public final static int CAT1 = 0;
    public final static int CAT2 = 1;
    public final static int CAT3 = 2;
    public final static int CAT4 = 3;
    private Question[] pool;
    private Question[] mcqs;
    private int currentCategory;
    private int currentQuestionIndex;
    private String pic;
    private String result;
    private String wrongquestion;

    //constructor
    public Quiz() {
        pool = new Question[POOLSIZE];
        mcqs = new Question[NOOFQUESTION];

        pool[0] = new Question(CAT1, "cat1_q1_question", "q1_choice1", "q1_choice2", "q1_choice3", "q1_choice4", 2);
        pool[1] = new Question(CAT1, "cat1_q2_question", "q2_choice1", "q2_choice2", "q2_choice3", "q2_choice4", 2);
        pool[2] = new Question(CAT1, "cat1_q3_question", "q3_choice1", "q3_choice2", "q3_choice3", "q3_choice4", 2);
        pool[3] = new Question(CAT1, "cat1_q4_question", "q4_choice1", "q4_choice2", "q4_choice3", "q4_choice4", 2);
        pool[4] = new Question(CAT1, "cat1_q5_question", "q5_choice1", "q5_choice2", "q5_choice3", "q5_choice4", 2);
        pool[5] = new Question(CAT2, "cat2_q1_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[6] = new Question(CAT2, "cat2_q2_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[7] = new Question(CAT2, "cat2_q3_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[8] = new Question(CAT2, "cat2_q4_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[9] = new Question(CAT2, "cat2_q5_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[10] = new Question(CAT3, "cat3_q1_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[11] = new Question(CAT3, "cat3_q2_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[12] = new Question(CAT3, "cat3_q3_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[13] = new Question(CAT3, "cat3_q4_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[14] = new Question(CAT3, "cat3_q5_question", "choice1", "choice2", "choice3", "choice4", 2);

        pool[15] = new Question(CAT4, "cat3_q1_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[16] = new Question(CAT4, "cat3_q2_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[17] = new Question(CAT4, "cat3_q3_question", "choice1", "choice2", "choice3", "choice4", 2);
        pool[18] = new Question(CAT4, "cat3_q4_question", "choice1", "choice2", "choice3", "choice4", 3);
        pool[19] = new Question(CAT4, "cat3_q5_question", "choice1", "choice2", "choice3", "choice4", 2);
    }

    public void setupMCQs(int cat) {
        currentCategory = cat;
        int j = 0;
        for (int i = 0; i < pool.length; i++) {
            if (pool[i].getCategory() == currentCategory) {
                mcqs[j] = pool[i];
                j++;
            }//end if
        }//end for
    }

    public String getCurrentCategory() {
        if (currentCategory == CAT1) {
            return "Category 1";
        }
        if (currentCategory == CAT2) {
            return "Category 2";
        }
        if (currentCategory == CAT3) {
            return "Category 3";
        } else {
            return "Category 4";
        }
    }

    public void nextCategory() {
        currentCategory++;
    }

    public void nextQuestion() {
        currentQuestionIndex++;
    }

    public boolean isLastQuestion() {
        if (currentQuestionIndex == mcqs.length) {
            return true;
        } else {
            return false;
        }
    }

    public int getCurrentQuestionIndex() {
        return currentQuestionIndex;
    }

    public Question getCurrentQuestion() {
        return mcqs[currentQuestionIndex];
    }

    public void setSelectedAnswer(int ans) {
        mcqs[currentQuestionIndex].setSelected(ans);
    }

    public void setPic(String p) {
        pic = p;
    }

    public String getPic() {
        return pic;
    }

    public String getResult() {
        int score = 0;
        int j = 0;
        for (int i = 0; i < mcqs.length; i++) {
            if (mcqs[i].getCorrect() == mcqs[i].getSelected()) {
                score++;
            }
            if (mcqs[i].getCorrect() != mcqs[i].getSelected());
            mcqs[i] = mcqs[j];
            mcqs[j].getQuestionText();
        }
        result = "You've answered  " + "\t" + score + " questions correctly" +
                "\n You've chosen the wrong answer(s) for the following question(s)" + "\n" + mcqs[j].getQuestionText();

        return result;
    }//end of Quiz Class
}

the result method is the part that I need to know how cos this will be used in the main application program.

I really hope someone can give me some pointers. Am very lost. Tks.

[mtyoung]

if (mcqs[i].getCorrect() != mcqs[i].getSelected());
why ";" present?

[Kareng]

Thanks so much for taking the time to help me like this.

I have changed the code as follows :-

 public String getResult() {
        int score = 0;
        int j = 0;
        for (int i = 0; i < mcqs.length; i++) {
            if (mcqs[i].getCorrect() == mcqs[i].getSelected()) {
                score++;
            if (mcqs[i].getCorrect() != mcqs[i].getSelected()){
            mcqs[i] = mcqs[j];
            mcqs[j].getQuestionText();
            }
            result = "You've answered  " + "\t" + score + " questions correctly" +
                "\n You've chosen the wrong answer(s) for the following question(s)" + "\n" 
                + mcqs[j].getQuestionText();
            }}
        return result;
    }}

However, when I run it, the result is blank. I wanted it to appear the question text for that particular question which is in my array.

Do you mind show me how to change my code in the way that will do that?

Thanks in advance.

[Kareng]

Hi, I thought I better post up the front part of the quiz as well so that you may advise me how to write the code which will draw out the wrong questions in text.

import javax.swing.*;

public class Question {//Question Class
public static final int NOT_SELECTED = -1;
public static final int NUMOFCHOICES = 4;

private int category;
private String questionText;
private String[] choices = new String[NUMOFCHOICES];
private int correct;
private int selected;
private int wrong;

//constructor
Question(int category, String questionText, String c1, String c2, String c3, String c4,
int correct) {

this.category = category;
this.questionText = questionText;
choices[0] = c1;
choices[1] = c2;
choices[2] = c3;
choices[3] = c4;
this.correct = correct;
this.selected = NOT_SELECTED;
}

public int getCategory() {
return category;
}

public String getQuestionText() {
return questionText;
}

public String[] getChoices() {
return choices;
}

public String getChoicesStr() {
String s = "";
for(int i = 0 ; i < choices.length ; i++) {
s += "(" + (i + 1) + ") " + choices[i] + "\n";
}
return s;
}


public int getCorrect() {
return correct;
}

public void setSelected(int selected) {
this.selected = selected;
}

public int getSelected() {
return selected;
}
}
//end of Question class

[Fubarable]

Hello,

One problem I see is the location of where your creating your result String. Proper indentation will point out to you much more easily that it's not sitting in the right location with reference to your if blocks and for loops:

  public String getResult() {
    int score = 0;
    int j = 0;
    String result = "";
    for (int i = 0; i < mcqs.length; i++) {
      if (mcqs[i].getCorrect() == mcqs[i].getSelected()) {
        score++;
        if (mcqs[i].getCorrect() != mcqs[i].getSelected()) {
          mcqs[i] = mcqs[j];
          mcqs[j].getQuestionText();
        }
        result = "You've answered  "
            + "\t"
            + score
            + " questions correctly"
            + "\n You've chosen the wrong answer(s) for the following question(s)"
            + "\n" + mcqs[j].getQuestionText();
      }
    }
    return result;
  }

You want to change this so that the result string is created only after you've iterated through all questions -- after the for loop.

Hope this helps. Also, I placed code tags in your post number 3 to aid readability and will leave it to you to place them in post number four (please see my signature). Please do so, since it makes reading your code and thus understanding your question much easier to do.

[Kareng]

I have tried your method. However, it doesn't give the desired output.

May be I didn't say it correctly.

The program is supposed to let the user choose the category, thereafter, select the questions, there are 5 questions.

N so, it will tells you what is your score and tells you in that category, which questions you got wrong.