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JavaScript

Posted by Chris Reich
Chris Reich
15,163 Points

Program stopping after for loop.

Here is my code: For some reason nothing is printed to the page. However, if I put the print('You got ' + numQuestionsCorrect + 'questions right.'); inside the for loop it prints out three times. I just want it printed once at the end. How can I do this?

var question_Answer = [
  ['What is the capital of CA?', 'Sacramento'],
  ['How many planets in our solar system','7'],
  ['What position did MJ play?','Forward']
];

var numQuestionsCorrect = 0;
var numQuestionsWrong = 0;

for (i = 0; i <= question_Answer.length; i+=1) {
    guess = prompt(question_Answer[i][0]);
  if (guess === question_Answer[i][1]) {
    numQuestionsCorrect+=1;
  } else {
    numQuestionsWrong+=1;
  } 
}

print('You got ' + numQuestionsCorrect + 'questions right.');

function print(message) {
  document.write(message);
}
Jacob Mishkin
Jacob Mishkin
23,118 Points

edited for formatting.

1 Answer

Gina Scalpone
Gina Scalpone
21,330 Points

There's an error in your for loop:

i <= question_Answer.length

There shouldn't be an equals sign in your loop condition because that means i will go to 3. Because arrays are zero-based, even though question_Answer has a length of 3, the indexes will be 0, 1, 2. Basically your loop is looking for question_Answer[3][0] when it doesn't exist. Remove the equals sign and it will work.

for (i = 0; i < question_Answer.length; i+=1)