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JavaScript

Ivan Marchenko
Ivan Marchenko
8,962 Points

So, what's up with my code, it wont print the last line.

var qa = [
    ['what is 1+1', 2],
    ['what is 1+2', 3],
    ['what is 1+3', 4]
];
var correctA = 0;
var q;
var a;


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

for ( var i = 0; i <= qa.length; i +=1) {
    q = parseInt(prompt(qa[i][0]));
    a = qa[i][1];
if ( a === q ){
    print('<p>Correct answer</p>');
    correctA +=1;
}else {
    print('wrong answer </br>');
    correctA -=1;
}

}

print('<h2>Correct answers: ' + correctA + '</h2>');

2 Answers

Sean T. Unwin
Sean T. Unwin
28,690 Points

You need to change your for loop statement to run the same amount of times as qa.length.

Currently you have i = 0 and i <= qa.length. Since qa.length is equal to 3, the loop is attempting to run 4 times.

Two ways to fix this (choose one method from below):

  1. Set i to 1
  2. Have i < qa.length (i.e remove the equals sign, from "<=" to be "<")
Jon Kussmann
PLUS
Jon Kussmann
Courses Plus Student 7,254 Points

Hi,

Does it work if you move your print statement to just before your last '}'?

Ivan Marchenko
Ivan Marchenko
8,962 Points

it does, but it goes inside a loop

Ivan Marchenko
Ivan Marchenko
8,962 Points

I tried doing it with out a function and with counsole.log, nothing works. Seams like a program just stops as soon as it finished the loop

Jon Kussmann
Jon Kussmann
Courses Plus Student 7,254 Points

It does seem odd (sorry, it's been a while since I've dealt with Javascript). Just for fun... try wrapping that last print statement in a separate for loop that only runs once.