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

Posted by andrew schoenherr
andrew schoenherr
8,427 Points

cant figure out why this wont work....

please help

script.js 
for ( i = 2; 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>
andrew schoenherr
andrew schoenherr
8,427 Points

question is... 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.

5 Answers

Daniel Newman
Daniel Newman
Courses Plus Student 10,715 Points

What you have done is infinity loop with error in statement:

for ( i = 2; i <= 24; i + 2; )

First of all, there must be only two ";" instead of yours three. The last one break your code.

The second is incremental "step statement ". It should be "i +=2" or "i = i + 2". Your expression will not change "i" variable and the loop become infinity.

Third - where did you define "i" var?

for ( i = 2; i <= 24; i += 2 )

Now it will work!

Jennifer Crawshaw
Jennifer Crawshaw
17,878 Points
Jennifer Crawshaw
Jennifer Crawshaw
17,878 Points

It looks like you just have a syntax error! You don't need the semicolon after the i + 2 statement, and you can write that as i += 2

That should work!

andrew schoenherr
andrew schoenherr
8,427 Points
andrew schoenherr
andrew schoenherr
8,427 Points

Thank you Daniel! And thank you for some explanation as to why I was wrong!

darrin allen
seal-mask
.a{fill-rule:evenodd;}techdegree
darrin allen
Full Stack JavaScript Techdegree Student 1,798 Points
darrin allen
.a{fill-rule:evenodd;}techdegree
darrin allen
Full Stack JavaScript Techdegree Student 1,798 Points

i had to use a while loop

var i = 2; while ( i <=24) { console.log(i); }

Omar kelsaw
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree
Omar kelsaw
Front End Web Development Techdegree Student 2,855 Points
Omar kelsaw
.a{fill-rule:evenodd;}techdegree
Omar kelsaw
Front End Web Development Techdegree Student 2,855 Points 
var j = 'evenNumber';
for ( var j = 2; j <= 24; j += 2 ) {
  console.log( j );
}

MAKE SURE YOU 'CONSOLE.LOG' j