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

Posted by Adam Fields
Adam Fields
4,487 Points

Create a for loop that logs the numbers 4 to 156 to the console. To log a value to the console use the console.log( )

what am I doing wrong?

script.js 
var num;
for(var i=4; i<=156;+=1)
  num+=1 + i;
    console.log(num);
}

2 Answers

Steven Parker
Steven Parker
231,261 Points
Steven Parker
Steven Parker
231,261 Points

I don't understand those calculations with "num", but you really don't need "num" at all. Just log the loop variable "i".

But you also have a syntax error in the final "for" loop clause: instead of "+=1" you need "i+=1" (to increment "i").

I'll bet you can get it now without an explicit code spoiler.

Adam Fields
Adam Fields
4,487 Points

thank you steven I figured it out thank you .

Kieran Barker
Kieran Barker
15,028 Points
Kieran Barker
Kieran Barker
15,028 Points

Hey Adam,

You're close! This is the correct code for this challenge:

for ( var i = 4; i <= 156; i++ ) {
  console.log( i );
}

What this code is doing is as follows:

  • Initializing a counter variable with the value 4.
  • Before each loop iteration, the JavaScript interpreter checks to see if the current value of i (which will be 4 the first time around) is less than 156. If it is, then the loop will run.
  • The JavaScript interpreter executes everything inside the code block — that’s everything inside the curly braces. In this case, the current value of i is logged to the console each time the loop runs.
  • At the end of the loop, the counter variable -- i -- is updated by 1. So the next time around it will be 5. The loop will stop running when the condition is no longer true, i.e. when i is no longer less than 156.

A quick note...

  • I used ++ to increcement i, but i += 1 will do the same thing.

Please let me know if you have any questions!

~ Kieran