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

Posted by Stephen Chamroeun
Stephen Chamroeun
7,095 Points

Build a Quiz: Review my code please?

Hey everyone! This is my code below into building a quiz generator and having a loop go through each question until it's finished. I think it does have some refactoring that does need to be done because when the final page loads after all questions are asked, I do get an undefined statement coming right before either the correct or incorrect questions statements. I messed around with the code for quite a bit before I got what I wanted...

var questions = [
  ['1. What is the name of a snake programming language?','python'],
  ['2. What is the name of the program that sounds like a gem?','ruby'],
  ['3. What is the name of the program that sounds like coffee?','javascript']
];

var correctAnswers = 0;
var correctQuestions;
var incorrectQuestions;


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

for ( var i = 0; i < questions.length; i += 1 ) {
  var guess = prompt(questions[i][0]);
  if ( guess.toLowerCase() === questions[i][1] ) {
   correctQuestions += '<p>' + questions[i][0] + '</p>';
   correctAnswers += 1;
  } else if ( guess.toLowerCase() !== questions[i][1] ) {
   incorrectQuestions += '<p>' + questions[i][0] + '</p>';
  }   
} 

print('<p>You got ' + correctAnswers + ' question(s) right.</p>' );
print('<p>You got these questions correct: </p>' + '<p>' + correctQuestions + '</p>');
print('<p>You got these questions wrong: </p>' + '<p>' + incorrectQuestions + '</p>');

2 Answers

Calin Bogdan
Calin Bogdan
14,921 Points

Hello!

There are 2 variables you're not initializing, but using: correctAnswers and incorrectAnswers. You can't add (+=) a value to their current value because they have none. Try initializing them with an empty string ('').

Stephen Chamroeun
Stephen Chamroeun
7,095 Points

Thank you so much. I highly appreciate you responding quickly there. But yes, I went ahead and put a value of an empty string for the variable and it worked out perfectly fine :).

Juglair Benato
seal-mask
.a{fill-rule:evenodd;}techdegree
Juglair Benato
Full Stack JavaScript Techdegree Student 6,159 Points
Juglair Benato
.a{fill-rule:evenodd;}techdegree
Juglair Benato
Full Stack JavaScript Techdegree Student 6,159 Points

I came up with this on my own, can you take a look ? :

function print(message) {
  document.write(message);}
var questions = [
  ['Capital of the United States ?', 'washington'],
  ['Capital of Brazil?', 'brasilia'],
  ['Capital of Ireland ?','dublin']
];var correctAwnsers = [];var wrongAwnsers =[];
//asking questions
for (i=0; i<3; i+=1){
anwser = prompt (questions[i][0]);
  if ( anwser.toLocaleLowerCase() === questions[i][1] )
  {correctAwnsers += '<li>'+ questions[i], + '</li>';} else {wrongAwnsers+= '<li>'+ questions[i], + '</li>';}
}
//printing out values
if (wrongAwnsers) {
print ('<h1>You got this ones wrong : </h1>')  
print (wrongAwnsers);
}
if (correctAwnsers){
print ('<h1>You got this ones right : </h1>')
print (correctAwnsers);
}```