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

Meshach Ojeda
Meshach Ojeda
8,276 Points

getting error:quiz.js:17 Uncaught TypeError: Cannot read property '0' of undefined at quiz.js:17

For some reason my code is not referencing the questions in the arrays index of 0 which is the questions. I am receiving error:quiz.js:17 Uncaught TypeError: Cannot read property '0' of undefined at quiz.js:17 I coded it exactyly like the video. Code is below

Meshach Ojeda
Meshach Ojeda
8,276 Points
var questions = [
    ['How many stated are in the US?', 50],
    ['How many continents are there?', 7],
    ['How many legs does an insect have?', 6]
];
    var correctAnswers = 0;
    var question;
    var answer;
    var response;
    var html;

function print(message) {
  document.write(message);
}

for( var i = 0; questions.length; i += 1) {
    question = questions[i][0];
    answer = questions[i][1];
    response = parseInt(prompt(question));
if (response === answer){
        correctAnswers +=1;
    }
}

html = "You got " + correctAnswers + " question(s) right.";
print(html);

1 Answer

Marco Cornejo
Marco Cornejo
3,394 Points

Hi, you forgot to add 'i <' at Line 16 in the For conditional, it should be:

for( var i = 0; i< questions.length; i += 1) {

It should work now.