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

Posted by Franklyn Gregory
Franklyn Gregory
12,098 Points

The code below logs all of the even numbers from 2 to 24 to the JavaScript console. However, there's a lot of redundant

I've been at this, and it's killing me I can't figure it out.

script.js 
for (  i = 2; i <= 25; i++) {
    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>
Dale Sellers
Dale Sellers
6,613 Points

I figured it out with the help of this MDN page: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for

This is what worked for me:

for (var i = 2; i < 25; i += 2) { console.log(i); }

9 Answers

Rachel Lev
Rachel Lev
14,583 Points
Rachel Lev
Rachel Lev
14,583 Points

You have to add 2 to i in order to get the even numbers, and i should be less or equal to 24 not 25:

for (i = 2; i <= 24; i += 2) {
console.log(i);
}
Adam Beer
Adam Beer
11,314 Points
Adam Beer
Adam Beer
11,314 Points

No one learns from the finished code.

Tadjiev Codes
Tadjiev Codes
9,626 Points
Tadjiev Codes
Tadjiev Codes
9,626 Points

Why do we need += in the end of the code within () ? Thanks

Justyna Szofinska
Justyna Szofinska
6,178 Points
Justyna Szofinska
Justyna Szofinska
6,178 Points 
for ( let i = 2; i <= 24; i += 2) {
console.log ( i );
}

You need to add variable 'let'. I also had problem to finished it because i didn't erase previous code (console.log(2) console.log(4)... ect)

Andrew Duty
Andrew Duty
4,856 Points
Andrew Duty
Andrew Duty
4,856 Points

This is what got it for me, had everything right expect the "let"

Adam Beer
Adam Beer
11,314 Points
Adam Beer
Adam Beer
11,314 Points

Challenge Task 1 of 1

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.

console.log(2);
console.log(4);
console.log(6);
console.log(8);
and so on...

And that's how your code work:

for (var i = 2; i <= 25; i++) { // In other words, i++ equal to i += 1
    console.log(i);

}

//the output
console.log(2);
console.log(3);
console.log(4);
console.log(5);

You are so close but it grows badly. This should be corrected and i <= 24. Hope this help.

Gheon Steenkamp
Gheon Steenkamp
458 Points
Gheon Steenkamp
Gheon Steenkamp
458 Points

None of these codes work on this discussion

Kyffin Richmond
Kyffin Richmond
2,534 Points
Kyffin Richmond
Kyffin Richmond
2,534 Points

Solved: The code uses a loop to display even numbers from 2 to 24. It starts at 2 and adds 2 repeatedly until it reaches 24, showing all the even numbers in between.

for (let i = 2; i <= 24; i += 2) {
  console.log(i);
}
Faiz Hamdan
Faiz Hamdan
5,215 Points
Faiz Hamdan
Faiz Hamdan
5,215 Points 
for ( var I = 2; I <= 24; i+=2 ) {
 console.log(i);
}

Hope this help Cheers!

Adam Beer
Adam Beer
11,314 Points
Adam Beer
Adam Beer
11,314 Points

And again, No one learns from the finished code. Second, your first two I is capitalized, and the last is lowercase, why? Now your code doesn't work.

Kamal Ghimire
Kamal Ghimire
12,143 Points
Kamal Ghimire
Kamal Ghimire
12,143 Points

Here the problem you should clear the coding area first and then start writing your loop code.

Celia Tawembe
Celia Tawembe
5,598 Points
Celia Tawembe
Celia Tawembe
5,598 Points

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

Sean White
Sean White
5,537 Points
Sean White
Sean White
5,537 Points

SyntaxError: script.js: Unexpected token < (1:18)

I typed this in

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

I got the above error every time until I copied and pasted it from Celia's answer. It is exactly the same code, I checked it multiple times. But when I typed it in, I get the above error. Copy and paste it's fine. This is the second question this has happened for.