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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops Create a for Loop

Posted by Jessica Stout
Jessica Stout
4,828 Points

HELP! This for loop is confusing me!

I am lost as to how to list the random number from 4-156 using a for loop. What am I missing? Should I add another variable? I'm so stuck! Any help would be GREATLY appreciated! Thank you!!!!

script.js 
for (var i=1; i<157; i+=1) {
}
console.log(i);

4 Answers

Zach Allan
Zach Allan
19,452 Points

Firstly, you need to put console.log(i) inside your for loop. Like this:

for (var i=1; i<157; i+=1) {
  console.log(i);
}

var i=1 is your initializer. It sets i (the index) to be 1.

i<157 is your condition. The loop keeps going until that condition is no longer true.

i+=1 is your increment. It keeps adding 1 to the previous number.

The for loop will break once it has reached 157. As soon as i gets to 157 then the condition is no longer true and the console.log will no longer get executed. So basically your loop will print out the numbers 1-156.

Hope that helps! :)

Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,671 Points
Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,671 Points

Good explanation – however, in this case, it should be i = 4;.

Jayden Spring
Jayden Spring
8,625 Points
Jayden Spring
Jayden Spring
8,625 Points

This look is not generating a random number simply iterating through I until its value is less than 157. Also to see an output you need the console log inside the for statement.

To generate random number between 0-157 use something like this; Math.floor(Math.Random() * 157)

Jayden

Jessica Stout
Jessica Stout
4,828 Points
Jessica Stout
Jessica Stout
4,828 Points

OH! I stated the task incorrectly- I'm sorry. I meant I need to log all the numbers from 4 to 156 in the console. Using the for loop.
What component am I missing?

Zach Allan
Zach Allan
19,452 Points

Just change i=1 to i=4

Zach Allan
Zach Allan
19,452 Points

And don't forget to put your console.log(i) inside the curly braces of the for loop.

Answer:

for (var i=4; i<157; i+=1) {
  console.log(i);
}
Jessica Stout
Jessica Stout
4,828 Points
Jessica Stout
Jessica Stout
4,828 Points

Fantastic!!!! Thank you so very much!!!!! That helps tremendously!
I appreciate your quick reply! This was driving me insane!

Zach Allan
Zach Allan
19,452 Points

No problem! Haha it's great when you finally figure something out! Glad I could help :)