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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 2 Solution

Brendan Moran
Brendan Moran
14,052 Points

My quiz with one small improvement (prevent hanging/empty category)

After I adjusted my code to Dave's specs from what I had before (I had it working, albeit in a more complicated way, using nodes both lists and their headlines), I noticed room for one small improvement: preventing an empty category just in case no questions are answered wrong or no questions are answered right. Towards the bottom of the code, I entered a single-line comment about it.

var answersCorrect = 0;
var question;
var answer;
var response;
var html;

var rightAnswers = [];
var wrongAnswers = [];

var questions = [
  ['What is the capitol of Rhode Island?', 'Providence'],
  ['What is your cat\'s name?', 'Baxter'],
  ['Who is Superman?', 'Clark Kent']

function print(message) {
  var outputDiv = document.getElementById('output');
  outputDiv.innerHTML = message;

function printList(arr) {
  var listHTML = "<ul>";
  for (var i = 0; i < arr.length; i += 1) {
    listHTML += "<li>" + arr[i] + "</li>";
  listHTML += "</ul>";
  return listHTML;

for (i = 0; i < 3; i += 1) {
  question = questions[i][0];
  answer = questions[i][1];
  response = prompt(question);
  if (response.toLowerCase() === answer.toLowerCase()) {
    answersCorrect += 1;
  } else {

html = 'You got ' + answersCorrect + ' right.';
if (rightAnswers.length > 0) { // If statement to prevent empty category in case of no answers right or no answers wrong
  html += "<h2>You got the following questions right:";
  html += printList(rightAnswers);
if (wrongAnswers.length > 0) {
  html += "<h2>You got the following questions wrong:";
  html += printList (wrongAnswers);