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

kg10
kg10
7,911 Points
Posted by kg10
kg10
7,911 Points

Alternative solution

I still find it very hard to understand if alternative solutions are inefficient in some way or it's just it - an alternative answer... Any tips are very much appreciated!

let quiz = [
    ['Which country does opera singer Pavarotti come from?', 'Italy'],
    ['Which swimming stroke is named after an insect?', 'Butterfly'],
    ['What is a female deer called?', 'Doe']
];
let guess;
let correct = [];
let wrong = [];

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

function printAnswers(answer) {
    let listHTML = '<ol>';
    for (let i = 0; i < answer.length; i += 1) {
        listHTML += '<li>' + answer[i] + '</li>';
    }
    listHTML += '</ol>';
    return listHTML;
}

for (let i = 0; i < quiz.length; i += 1) {
    guess = prompt(quiz[i][0]);
    guess = guess.toUpperCase();
    if ( guess === quiz[i][1].toUpperCase() ) {
        correct.push(quiz[i][0]);
    } else {
        wrong.push(quiz[i][0]);
    }
}

html = `<p>You got ${correct.length} question(s) right.</p>`;
html += `<h2>You got these questions correct:</h2>`;
html += printAnswers(correct);
html += `<h2>You got these questions wrong:</h2>`;
html += printAnswers(wrong);

print(html);

2 Answers

Zimri Leijen
Zimri Leijen
11,835 Points

In most cases it hardly matters.

unless you're working with really big data, or write extremely inefficient code, the processing power we have available nowadays makes it pretty irrelevant.

In most cases, developer time is more valuable than process time, in other words, the time a developer would spend to optimize the program is more expensive than the hypothetical time saved running the program.

There are of course cases where optimization matters, but you probably wouldn't be using javascript there anyway.

James Croxford
James Croxford
12,723 Points
James Croxford
James Croxford
12,723 Points

Mine is similar to yours. I used the same prompt style as yourself (not creating a separate variable).

  guess = prompt(quiz[i][0]);

I added a few extras (such as checking for blank responses from the user), but the main difference from for me was using template literals over standard string literals, as to me they're neater and more readable.

I think ultimately though as Zimri says most of the possible optimisations, whatever they may be, either I'm not aware of yet, aren't necessary for this type of basic JS file, or in some cases can offer a trade off (less readable code to others/yourself upon returning to it)?

Zimri Leijen
Zimri Leijen
11,835 Points

readability and maintainability are indeed often the most important thing to keep in mind.