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

Gavin Broekema
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Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points
Posted by Gavin Broekema
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Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points

45 line solution. Feedback please?

var questions = [
  ["Which language is typically used to structure a webpage?", "html"], 
  ["Which language is typically used to add presentation to a webpage?", "css"], 
  ["Which language is typically used to add behavior to a webpage?", "javascript"]
];
var correct = 0;
var incorrect = 0;
var answer;
var right = [];
var wrong = [];

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

function grade (marks) {
  var response = "";
  response += '<ol>';
  for (var i = 0; i < marks.length; i++) {
    response += '<li>' + marks[i] + '</li>';
  }
  response += '</ol>';
  print(response);
}

for (var i = 0; i < questions.length; i += 1) {
  answer = prompt(questions[i][0]);
  answer = answer.toLowerCase();
  if (answer === questions[i][1]) {
    correct++;
    right.push(questions[i][0]);
  } else {
    wrong.push(questions[i][0]);
    incorrect++;
  }
}

print('<p>You got ' + correct + ' question(s) correct.<br>');
if (correct > 0) {
  print('<strong><p>You got these questions correct: </p></strong>');
  grade(right);
} else if (incorrect > 0) {
  print('<strong><p>You got these questions incorrect: </p></strong>');
  grade(wrong);
}

I decided to remove the opposing statement if all questions were answered correctly/incorrectly for a little extra challenge. Tried to answer this challenge as succinctly as possible, but there's obviously always room for improvement! Please let me know if/how I could make this program more concise (while keeping it maintainable/readable of course). Thanks!

2 Answers

Sergio Alen
Sergio Alen
26,726 Points
Sergio Alen
Sergio Alen
26,726 Points

You can also condense your var declarations:

var questions = [
  ["Which language is typically used to structure a webpage?", "html"], 
  ["Which language is typically used to add presentation to a webpage?", "css"], 
  ["Which language is typically used to add behavior to a webpage?", "javascript"]
],
correct = 0,
incorrect = 0,
answer,
right = [],
wrong = [];
alastair cooper
alastair cooper
30,617 Points
alastair cooper
alastair cooper
30,617 Points

very good.

You could condense this:

 var response = "";
  response += '<ol>';

to 

 var response = '<ol>';

not much different, but 1 less line to compile