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

Cody Selman
Cody Selman
7,643 Points

My Solution to Build a Quiz Challenge Part 1

Here is my solution to this challenge: https://w.trhou.se/zkpp6wbqjx

Here's the JavaScript:

var numberCorrect = 0;
var qAndA = [ 
  ['What is 2 * 3?', '6'],
  ['What is 49 / 7?', '7'],
  ['What is 7 + 5?', '12']
];

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

for ( var i = 0; i < qAndA.length; i++){
 var userAnswer = prompt( qAndA[i][0] ); 
  if ( userAnswer === qAndA[i][1] ){
    numberCorrect++;
  }
}

print('You answered ' + numberCorrect + ' out of ' + qAndA.length + ' questions correctly.');

Let me know if you had any comments or improvements. Thank you.

Joshua Petry
Joshua Petry
6,313 Points

Here's my solution!

var correctQuestions = "";
var incorrectQuestions = "";

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

var questions = [
  ['How many states are there?', '50'],
  ['How old am I?', '27'],
  ['What year was I born?', '1991']
];

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

print('<h2>You got these questions right:</h2>' + correctQuestions + '<h2>You got these questions wrong:</h2>' + incorrectQuestions);

5 Answers

another version with more conditions

// instantiate global variables (counters)
var qCounter = 0;
var numRight = 0;
var numWrong = 0;

//create arrays for data
var rightAnswer = [];
var wrongAnswer = [];
var questionPool = [
  ['158=___ + 106. What number will come in the blank to make the number sentence true?', '52'],
  ['Which moon is larger than Mercury?', 'io'],
  ['What is the name of the little dragon in the animated movie Mulan?', 'mushu'],
  ['What is the name of the prison in the film The Rock?', 'alcatraz'],
  ['Give another name for the study of fossils?', 'paleontology'],
  ['Which insects cannot fly, but can jump higher than 30 cm?', 'flea'],
  ['Which plant does the Canadian flag contain?', 'maple'],
  ['Which is the largest desert on earth?', 'sahara'],
  ['What is the largest state of the United States?', 'alaska'],
  ['What is the capital of the American state Hawaii?', 'honolulu'],
];

// functions to be used
// updated print function to html doc
function print(message) {
  var outputDiv = document.getElementById('output');
  outputDiv.innerHTML = message;
}
//calculate percentage
function calcPercent() {
  var total = numRight + numWrong;
  return numRight / total * 100;
}
//gather questions and put in html list format
function listQuestions(arr) {
  var html = '<ol>';
  for (var i = 0; i < arr.length; i++) {
    html += '<li>' + arr[i] + '</li>';
  }
  html += '</ol>';
  return html;
}

//main program. Iterate through array. Bring answer to lower case. Count right/wrong.Push to appropriate arrays
for (var i = 0; i < questionPool.length; i++) {
  var question = questionPool[i][0];
  var answer = questionPool[i][1];
  var askQuestion = prompt(question.toLowerCase());
  if (answer === askQuestion) {
    numRight++;
    rightAnswer.push(question);
  } else {
    numWrong++;
    wrongAnswer.push(question);
  }
}
// testing values. Note - only for dev testing
console.log('Testing Number right - '+numRight);
console.log('Testing Number wrong - '+numWrong);

//print html will depend on conditions
html = '<p>Here is your results:</p>';
if (numRight > 1 && numRight <10){
  html += 'You got ' + numRight + ' correct questions and ' + numWrong + '  wrong questions. '+ calcPercent() + '%';
  html += '<h2> Here is a list of questions you got right';
  html += listQuestions(rightAnswer);
  html += '<h2> Here is a list of questions you got wrong';
  html += listQuestions(wrongAnswer);
} else if (numRight == 1){
  html += 'You only got ' + numRight + ' correct question and ' + numWrong + ' wrong. ' + calcPercent() + '%';
  html += '<h2> Here is the question you got right';
  html += listQuestions(rightAnswer);
  html += '<h2> Here is a list of questions you got wrong';
  html += listQuestions(wrongAnswer);
} else if(numRight == 0) {
  html += 'You did not get any correct questions. Please try again next time. '+ calcPercent() + '%';
  html += '<h2> Here is a list of all the questions you got wrong';
  html += listQuestions(wrongAnswer);
} else {
  html += 'You got all ' + numRight + ' questions correct. Good Job! '+ calcPercent() + '%';
  html += '<h2> Here is a list of all the questions you got right';
  html += listQuestions(rightAnswer);
}
//doc write to div built html variable
print(html);
Kevin Michie
Kevin Michie
6,554 Points

Here is my solution that handles string vs number:

var questions= [
  ['What is your name?', 'kevin'],
  ['Who teaches this class?', 'dave mcfarland'],
  ['What is the meaning of life?', 42]
]

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

var correctAnswerCounter = 0;

var correctQuestions = [];

var incorrectQuestions = [];

function evaluator(questionArray) {
  var html= '<ol>';
  for(var i = 0; i < questionArray.length; i += 1) {
      html += '<li>' + questionArray[i] + '</li>';
    }
  html += '</ol>';
  print(html);
}

function quiz(questions) {
  for(var i = 0; i < questions.length; i += 1){
    answer = prompt(questions[i][0]);   
    if (typeof answer === "string" && isNaN(parseInt(answer))){
     answer = answer.toLowerCase(); 
    } else {
     answer = parseInt(answer); 
    }
    if(answer === questions[i][1]){
      correctAnswerCounter +=1;
      correctQuestions.push(questions[i][0]);
    } else{
      incorrectQuestions.push(questions[i][0]);
    }
  }

  print('<p>You got ' + correctAnswerCounter + ' question(s) right.</p>');

  print('<h3>You got these questions correct:</h3>');
  evaluator(correctQuestions);

  print('<h3>You got these questions wrong:</h3>');
  evaluator(incorrectQuestions);
}

quiz(questions);

my solution

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

//initial dimentional array questions with answers 
var quizQuestions = [
  ['How many states are in the U.S.?', '50'],
  ['How many legs does an insect have?', '6'],
  ['How many continents are there?', '7']
];

// need to make array collectors for right/wrong answers
var rightQ = [];
var wrongQ = [];

//counter for right/wrong answers 
var rightA = 0;
var wrongA = 0;

// iterate through dimentional array and push to collector array as well as add to counters
for (var i=0;i < quizQuestions.length; i++) {
  var answer = prompt(quizQuestions[i][0]);
  if (answer === quizQuestions[i][1] ) {
  rightA++;
  rightQ.push(quizQuestions[i][0]);
  }else {
  wrongA++;
    wrongQ.push(quizQuestions[i][0]);
  }

}

//function to collect array values and build html list to print
function collectQ(arrayQ){
html = '<ol>';
  for (var i=0; i < arrayQ.length; i++){
    html+= '<li>' + arrayQ[i] + '</li>';
  }
  html += '</ol>';
  print(html);
}


//print titles with final values using array data and function output
print('You got ' + rightA + ' question(s) right.');

print('<h2 style="font-weight: bold"> You got these question(s) right.</h2>');
    collectQ(rightQ);

print('<h2 style="font-weight: bold"> You Got these question(s) wrong.</h2>');
   collectQ(wrongQ);

Sorry for the weird code post - I followed the markdown for posting code and I got this

another version with added conditions

// instantiate global variables (counters)
var qCounter = 0;
var numRight = 0;
var numWrong = 0;

//create arrays for data
var rightAnswer = [];
var wrongAnswer = [];
var questionPool = [
  ['158=___ + 106. What number will come in the blank to make the number sentence true?', '52'],
  ['Which moon is larger than Mercury?', 'io'],
  ['What is the name of the little dragon in the animated movie Mulan?', 'mushu'],
  ['What is the name of the prison in the film The Rock?', 'alcatraz'],
  ['Give another name for the study of fossils?', 'paleontology'],
  ['Which insects cannot fly, but can jump higher than 30 cm?', 'flea'],
  ['Which plant does the Canadian flag contain?', 'maple'],
  ['Which is the largest desert on earth?', 'sahara'],
  ['What is the largest state of the United States?', 'alaska'],
  ['What is the capital of the American state Hawaii?', 'honolulu'],
];

// functions to be used
// updated print function to html doc
function print(message) {
  var outputDiv = document.getElementById('output');
  outputDiv.innerHTML = message;
}
//calculate percentage
function calcPercent() {
  var total = numRight + numWrong;
  return numRight / total * 100;
}
//gather questions and put in html list format
function listQuestions(arr) {
  var html = '<ol>';
  for (var i = 0; i < arr.length; i++) {
    html += '<li>' + arr[i] + '</li>';
  }
  html += '</ol>';
  return html;
}

//main program. Iterate through array. Bring answer to lower case. Count right/wrong.Push to appropriate arrays
for (var i = 0; i < questionPool.length; i++) {
  var question = questionPool[i][0];
  var answer = questionPool[i][1];
  var askQuestion = prompt(question.toLowerCase());
  if (answer === askQuestion) {
    numRight++;
    rightAnswer.push(question);
  } else {
    numWrong++;
    wrongAnswer.push(question);
  }
}
// testing values. Note - only for dev testing
console.log('Testing Number right - '+numRight);
console.log('Testing Number wrong - '+numWrong);

//print html will depend on conditions
html = '<p>Here is your results:</p>';
if (numRight > 1 && numRight <10){
  html += 'You got ' + numRight + ' correct questions and ' + numWrong + '  wrong questions. '+ calcPercent() + '%';
  html += '<h2> Here is a list of questions you got right';
  html += listQuestions(rightAnswer);
  html += '<h2> Here is a list of questions you got wrong';
  html += listQuestions(wrongAnswer);
} else if (numRight == 1){
  html += 'You only got ' + numRight + ' correct question and ' + numWrong + ' wrong. ' + calcPercent() + '%';
  html += '<h2> Here is the question you got right';
  html += listQuestions(rightAnswer);
  html += '<h2> Here is a list of questions you got wrong';
  html += listQuestions(wrongAnswer);
} else if(numRight == 0) {
  html += 'You did not get any correct questions. Please try again next time. '+ calcPercent() + '%';
  html += '<h2> Here is a list of all the questions you got wrong';
  html += listQuestions(wrongAnswer);
} else {
  html += 'You got all ' + numRight + ' questions correct. Good Job! '+ calcPercent() + '%';
  html += '<h2> Here is a list of all the questions you got right';
  html += listQuestions(rightAnswer);
}
//doc write to div built html variable
print(html);
Doron Geyer
seal-mask
.a{fill-rule:evenodd;}techdegree
Doron Geyer
Full Stack JavaScript Techdegree Student 13,884 Points

Got the code to work fine but HTML formatting I have no idea what im doing, hoping at some point this fullstackJS course is going to cover html and css.

function print(message) {
  document.write(message);
}
var html = "<ol>";
var incorrectQ = [];
var correctQ = [];
var corAns = 0;
var questions=[
  ["which programming lanugage are we using?", "JavaScript"],
  ["which programming language is named after a snake?", "Python"],
  ["which programming language is named after a gemstone", "Ruby"]
]
for(i=0;i<questions.length;i+=1){
var ques = prompt(questions[i][0]);
  if(ques.toLowerCase() === (questions[i][1]).toLowerCase()){
    correctQ.push(questions[i][0]);
    corAns++
  }else if(ques.toLowerCase() !== (questions[i][1]).toLowerCase()){
    incorrectQ.push(questions[i][0]);
  }
}
print(`you got ${corAns} questions correct and ${questions.length - corAns} incorrect.<br>`);
print("<h1>you got the following questins correct</h1>"+ "<li>"+ correctQ.join(", ")+"</li>" + "</ol>");
print("<h1>you got the following questins incorrect</h1>" + incorrectQ.join(", ") + "</ol>");