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

Konrad Dziekonski
Konrad Dziekonski
7,798 Points
Posted by Konrad Dziekonski
Konrad Dziekonski
7,798 Points

code review

Hello,

I managed to finish the task, but I did not write a function to print the list I just used <br> tag, I know its more primitive ;] But my question is that I did not use the push method to add correct or incorrect answers to those extra arrays I have created, only +=. What implications it has? I am asking just for the future, because i assume that despite it is working, push method is for some reasons better, at least seems to be more sofisticated.

const quizz = [
  ['What is the polar bears skin color?', 'black'],
  ['What kind of horse can see up fron as good as from behind?', 'blind'],
  ['Which wheel is not in use while turning?', 'spare'],
  ['What month has 28 days?', 'every'],
  ['What rocks are in the ocean?', 'wet'],
];
let right = [];
let wrong = [];
let counterGood = 0;
let counterBad = 0;
let i;
function print(message) {
  document.write(message);
}

for (i=0; i<quizz.length; i+=1) {
  question = prompt(quizz[i][0]);
  question = question.toLowerCase();
  let answer = quizz[i][1];
  if (question === answer) {
    counterGood += 1;
    right += quizz[i][0] + '<br>';
  } else {
    counterBad += 1;
    wrong += quizz[i][0] + '<br>';
  }
  }
  print('<h1>You got ' + counterGood + ' questions right and ' + counterBad + ' wrong answers!</h1><br>');
  print('<h3>You answered those correctly:</h3> <br>' + right);
  print('<h3>You answered those incorrectly:</h3> <br>' + wrong);

Thanks!

2 Answers

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The variables "right" and "wrong" become strings when you use the "+=" operator to combine them with a string.

The "push" method would allow you to add string items onto them and keep them as arrays, but then you'd need a more sophisticated process to output them at the end.