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

How to fix this?

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
var counter = 1;
for (counter = 1; counter <= 12; counter * 2) {
  console.log(counter);
}
index.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

3 Answers

Jamie Reardon
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Jamie Reardon
Treehouse Project Reviewer

Don't overthink it. You can simplify this and reduce the code like so:

  • You don't need to create a variable outside of the loop, you can use the index variable defined in the loop that you should create for (var i = 2) in this case.
  • The initial value of the variable should be 2 since you want to print out from number 2, not 1.
  • Your condition's value should be 24, not 12 since you want the loop to end once the value of the variable is 24.
  • You don't need to multiply the number, you need to use the += operator to add the value on the right to the variable.
for (var i = 2; i <= 24; i += 2) {
  console.log(i);
}
Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 90,683 Points

For your exit experssion, which is the third item in the for loop try using counter += 2 in your rather than counter * 2.

Thank you so much.