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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 1 Solution

Kevin O'Brien
Kevin O'Brien
3,802 Points

Answers Don't Increment

Hi all,

I am trying to resolve with the following code, but somehow, I think my answers do not increment at correct or wrong ones.

I have used slightly different for loop, with prompt, but cannot understand where I am exactly failing. Here is the code

var quiz = [
  ["What's your name?", "Kevin"],
  ["Where do you live?", "Dublin"],
  ["What is your favourite food?", "Sushi"]

var answer;
var correctAnswer = 0;
var wrongAnswer = 0;
var html;

function print(message) {

for(var i = 0; i < quiz.length; i += 1) {
  answer = prompt(quiz[i][0]);
  if (answer === quiz[i][1]) {
    correctAnswer =+ 1;
      wrongAnswer =+1;


html = "You have answered " + correctAnswer + " questions correctly but you have answered " + wrongAnswer+ " questions wrongly.";


I could not understand the exact reason of Dave having the loop part as questions, so if anyone can assist on that, it would be very helpful.


  • Kevin

3 Answers

Gabriel Roberto Moreira Santos
Gabriel Roberto Moreira Santos
1,182 Points

If you're speaking about the "correctAnswer" and "wrongAnswer", the correct form to increment these numbers are [ correctAnswer += 1 ] or [ correctAnswer++ ] and not [ correctAnswer =+ 1 ].

Kevin O'Brien
Kevin O'Brien
3,802 Points

Thanks a lot, Gabriel!

I was surprised to see that it was such a basic mistake and slipped through my attention and made me think if the logic is flawed at the loop. Also, thank you for the rapid response!

Also noticed I made a small mistake at "quiz.length", which I found after looking to where you mentioned, regards!

Also it would help if you used answer.toLowercase and stored the answers in your array as lowercase, that way the answers are no longer case sensitive.