Quiz Score Calculator

Score a quiz by matching each question with the answer the user gave. The final result should include the count, total, percentage, and a simple message.

Write these functions:

isAnswerCorrect(question, userAnswer) should return true when the user's answer matches the correct answer.
countCorrectAnswers(questions, userAnswers) should match each question with its user answer and return the number correct.
calculatePercentage(correctCount, totalQuestions) should return the percentage score.
getResultMessage(percentage) should return a short message based on the percentage.
createQuizResult(questions, userAnswers) should return correctCount, totalQuestions, percentage, and message.

Sample checks:

const questions = [  { id: 1, correctAnswer: 'B' },  { id: 2, correctAnswer: 'A' },  { id: 3, correctAnswer: 'D' },  { id: 4, correctAnswer: 'C' },];const userAnswers = [  { questionId: 1, answer: 'B' },  { questionId: 2, answer: 'C' },  { questionId: 3, answer: 'D' },  { questionId: 4, answer: 'C' },];console.log(createQuizResult(questions, userAnswers));console.log(countCorrectAnswers(questions, userAnswers));console.log(calculatePercentage(3, questions.length));const partialAnswers = [{ questionId: 1, answer: 'B' }];console.log(createQuizResult(questions, partialAnswers));

Expected output:

txt

{ correctCount: 3, totalQuestions: 4, percentage: 75, message: "You passed" }375{ correctCount: 1, totalQuestions: 4, percentage: 25, message: "Keep practicing" }

If a user answer is missing, count that question as incorrect.

Solution

Solution:

function isAnswerCorrect(question, userAnswer) {  if (!userAnswer) {    return false;  }  return question.correctAnswer === userAnswer.answer;}function countCorrectAnswers(questions, userAnswers) {  let correctCount = 0;  for (const question of questions) {    const userAnswer = userAnswers.find((answer) => {      return answer.questionId === question.id;    });    if (isAnswerCorrect(question, userAnswer)) {      correctCount += 1;    }  }  return correctCount;}function calculatePercentage(correctCount, totalQuestions) {  if (totalQuestions === 0) {    return 0;  }  return (correctCount / totalQuestions) * 100;}function getResultMessage(percentage) {  if (percentage >= 80) {    return 'Great work';  }  if (percentage >= 60) {    return 'You passed';  }  return 'Keep practicing';}function createQuizResult(questions, userAnswers) {  const correctCount = countCorrectAnswers(questions, userAnswers);  const totalQuestions = questions.length;  const percentage = calculatePercentage(correctCount, totalQuestions);  return {    correctCount,    totalQuestions,    percentage,    message: getResultMessage(percentage),  };}const questions = [  { id: 1, correctAnswer: 'B' },  { id: 2, correctAnswer: 'A' },  { id: 3, correctAnswer: 'D' },  { id: 4, correctAnswer: 'C' },];const userAnswers = [  { questionId: 1, answer: 'B' },  { questionId: 2, answer: 'C' },  { questionId: 3, answer: 'D' },  { questionId: 4, answer: 'C' },];console.log(createQuizResult(questions, userAnswers));console.log(countCorrectAnswers(questions, userAnswers));console.log(calculatePercentage(3, questions.length));const partialAnswers = [{ questionId: 1, answer: 'B' }];console.log(createQuizResult(questions, partialAnswers));