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JavaScript JavaScript Arrays Multidimensional Arrays Build a Quiz Challenge – One Solution

James Thompson
James Thompson
2,475 Points

My solution to the challenge.

Here was my solution to the challenge. At first I was not for sure how to actually use the question part of the array so I ignored it with my implementation. Did anyone else try something similar?

// 1. Create a multidimensional array to hold quiz questions and answers const quiz_game = [ ["How many letters are in the color red?", "three"], ["How many letters are in the color orange?", "six"], ["How many letters are in the color blue?", "four"]

];

// 2. Store the number of questions answered correctly

/*

  1. Use a loop to cycle through each question
    • Present each question to the user
    • Compare the user's response to answer in the array
    • If the response matches the answer, the number of correctly answered questions increments by 1 */

let message; // initializing a variable to write a message. let correct_answer = 0; // initializing a variable to hold the correct amount of numbers.

answer_1 = prompt("How many letters are in the color red?"); answer_2 = prompt("How many letters are in the color orange?"); answer_3 = prompt("How many letters are in the color blue?");

for (let i = 0; i < 1; i++) {

if (!answer_1 || !answer_2 || !answer_3) { message = console.log("Please input answers to the quiz."); break; }
if (answer_1 === quiz_game[0][1]) { correct_answer += 1;

} if(answer_2 === quiz_game[1][1]) { correct_answer += 1;

} if(answer_3 === quiz_game [2][1]) { correct_answer += 1;

  }

}

message = console.log(You got ${correct_answer} questions correct!!);

// 4. Display the number of correct answers to the user

Simon Coates
Simon Coates
4,911 Points

You should be able to see what some other people were trying to do via the questions for that video. Even if they got stuck it might give you an insight into approaches taken. I don't think I've done that video series, but I decided to throw a (poorly tested) demo together. I came up with:

let correctAnswers = 0;
const quiz_game = [["some question", "34"], 
    ["some other question", "an army of badgers"]];

for (let i = 0; i <  quiz_game.length ; ) {
  let answer = prompt(quiz_game[i][0]);
  if(!answer){
     continue;
  } else  if (answer === quiz_game[i][1]) {
    correctAnswers++;
  }
  i++;
}
alert(`You got ${correctAnswers} questions correct!!`);

You seemed to be trying to do validation despite this not fitting well with your for loop. To do validation, i added a test on answer and manually performed the for loop's increment. If there's no answer, it continues and never gets to the i++ line to proceed to the next question.

1 Answer

This is my solution

const quiz = [ ['How many planets are in the Solar System', '8'], ['Which is the largest planet in the Solar System', 'JUPITER'], ['What planet is after Earth?', 'MARS'], ['How many continents are there?', '7'], ['How many legs does an insect have?','6'], ['What year was JavaScript created?', '1995']

];

// 2. Store the number of questions answered correctly

let correctAnswers = 0

//3. Use a loop to cycle through each question // - Present each question to the user // - Compare the user's response to answer in the array // - If the response matches the answer, the number of correctly // answered questions increments by 1

for (let i = 0; i < quiz.length; i++ ) { const askedQuestions = ${quiz[i][0]}; const quizAnswers = ${quiz[i][1]}; const response = prompt(${askedQuestions});

if (response.toUpperCase() === quizAnswers) { correctAnswers++;

    }     

}

//4. Display the number of correct answers to the user

document.querySelector('main').innerHTML = <h1>You have ${correctAnswers} correct answers!</h1>;