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JavaScript

Ivan Marchenko
Ivan Marchenko
8,962 Points
Posted by 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
28,688 Points
Sean T. Unwin
Sean T. Unwin
28,688 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
Jon Kussmann
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
Ivan Marchenko
Ivan Marchenko
8,962 Points

it does, but it goes inside a loop

Ivan Marchenko
Ivan Marchenko
8,962 Points
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
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.