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

Posted by Michael Wilson
Michael Wilson
1,782 Points

I need assistance with this for loop code

The error is telling me that the left side of this is not a reference. I don't understand. Please help.

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

1 Answer

Grace Kelly
Grace Kelly
33,990 Points
Grace Kelly
Grace Kelly
33,990 Points

Hi Michael, you've got the right idea just a couple of minor things.

In your code you have called the console.log() twice, which is not needed. Also you are incrementing the i value inside the for loop (console.log( i + 1) which is not needed as this is done inside the parenthesis when we declare the for loop, like so:

//declare the i variable, execute the loop while i <= 156, increment i by 1 on each iteration of the loop (e.g 4 + 1 = 5)
for (var i = 4; i <= 156; i += 1) { 
  console.log(i); //print out the value of i
}

Hope that helps!!

Michael Wilson
Michael Wilson
1,782 Points

Thanks again Grace,

I thought that was what I typed the first time. Ok.

Grace Kelly
Grace Kelly
33,990 Points
Grace Kelly
Grace Kelly
33,990 Points

no problem, haha don't worry that happens to me too sometimes and then i look back and see i made a minor mistake. Just so long as you learn from it and progress onwards don't sweat :)