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

Amber Wells
Amber Wells
Front End Web Development Techdegree Student 18,493 Points

Only Questions print. Can someone explain the error? The right and wrong lists don't print.

var questions = [ ['What time is noon?', '12'], 
                 ['How many is a few?', 3],
                 ['When is too early?', '6'] ];

var correctAnswers = 0
var question;
var answer;
var response;
var correct = [];
var wrong = [];

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

function buildList(arr) {
 var listHTML = '<ol>';
  for (var i = 0; i < arr.length; i += 1) {
   listHTML += '<li>' + arr[i] + '</li>'; 
  listHTML += '</ol>';
  return listHTML;
for (var i = 0; i < questions.length; i += 1) {
  question = questions[i][0];
  answer = questions[i][1];
  response = parseInt( prompt(question));
  if (response === answer) {
   correctAnswers += 1;
  } else {


html = "You got " + correctAnswers + " question(s) right.";
html += '<h2>You got these questions correct:</h2>';
html += buildList(correct);
html += '<h2>You got these wrong:</h2>';
html = buildList(wrong);

Moderator Edit: Added JavaScript markdown to code for correct formatting and highlighting in the Community. How-to for Markdown can be found in the Markdown Cheetsheet located below post and above "Post Answer" button.

1 Answer

Steven Parker
Steven Parker
229,920 Points

You just have a typo. On this line:

html = buildList(wrong);

You probably intended to have a concatenating assignment ("+=") but the plus sign is missing. So the normal assignment wipes out everything else that would be in the string.