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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops Refactor Using a Loop

Posted by William J. Terrell
William J. Terrell
17,403 Points

Code Challenge: Refactor Using a Loop

The question asks to do the following:

The code below logs all of the even numbers from 2 to 24 to the JavaScript console. However, there's a lot of redundant code here. Re-write this using a loop.

script.js 
console.log(2);
console.log(4);
console.log(6);
console.log(8);
console.log(10);
console.log(12);
console.log(14);
console.log(16);
console.log(18);
console.log(20);
console.log(22);
console.log(24);

My code is posted below.

Any help is appreciated.

Thanks!

script.js 
for ( var i = 1; i <= 24; i * 2 ) {
 console.log( i );
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

6 Answers

John Magee
John Magee
Courses Plus Student 9,058 Points

Two things

  1. You don't have to use var in a loop definition
  2. The third portion of your loop declaration needs to increment i - you need to INCREASE the value of i - the code you have written is not actually increasing i - it just returns the same number every time
Stephen Minotti
Stephen Minotti
4,114 Points
Stephen Minotti
Stephen Minotti
4,114 Points

This gave me trouble also. I went back in my notes to the first lesson on for loops and found the answer. The correct code is...

for ( i = 2; i <= 24; i += 2 ) { console.log ( i ); }

John Magee
PLUS
John Magee
Courses Plus Student 9,058 Points
John Magee
John Magee
Courses Plus Student 9,058 Points

I don't want to give you the entire answer, but my suggestion is to reread what the output should be and then take a look at what your function will output. The answer should become apparent.

William J. Terrell
William J. Terrell
17,403 Points

Well, I changed it to:

script.js 
for (var i = 2; i <= 24; i + 2) {
 console.log(i) 
}

And it killed Google when I tried running it in the console; so, is there something wrong with the < = 24 ? But I thought that part of the code told it to run until i < = 24 (meaning that, once i > 24, the code would stop).

Roberto Cardenas
Roberto Cardenas
10,478 Points
Roberto Cardenas
Roberto Cardenas
10,478 Points

i + 2 is missing something.

William J. Terrell
William J. Terrell
17,403 Points

I got it to work. I forget exactly the code I used; I think I changed 2 to a 1, but I was using i + number when I should have been using i += number. Once I changed it to +=, it worked!

Thanks!

kmorrison
kmorrison
5,090 Points
kmorrison
kmorrison
5,090 Points

thats the wrong answer

Caden Ingram
Caden Ingram
6,482 Points
Caden Ingram
Caden Ingram
6,482 Points

No it's not, he was clever enough to find that out.