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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Iterating through an Array

Posted by Stephen Santiago
Stephen Santiago
9,631 Points

Array & Loops Code Challenge - What am I doing wrong?!?!?!

I am supposed to Iterate each value in the Array "temperatures". Not sure what I am doing wrong exactly.

script.js 
var temperatures = [100,90,99,80,70,65,30,10];

function temp(temperatures) {

  for ( var i = 0, i < temperatures.length, i += 1 ) {
    console.log(temperatures[i]);
  }
}
temp(temperatures);
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Hugo Paz
Hugo Paz
15,622 Points
Hugo Paz
Hugo Paz
15,622 Points

Hi Stephen,

You have commas instead of semi colons in your for definition.

 for ( var i = 0, i < temperatures.length, i += 1 )

should be

 for ( var i = 0; i < temperatures.length; i += 1 )
Stephen Santiago
Stephen Santiago
9,631 Points

-_- I'm an idiot, thank you

Austin Lilley
Austin Lilley
5,727 Points
Austin Lilley
Austin Lilley
5,727 Points

I think this should do it for you:

var temperatures = [100,90,99,80,70,65,30,10];

function temp(temperatures) {

  for (var i = 0; i < temperatures.length; i ++ ) {
    console.log(temperatures[i]);
  }
}
temp(temperatures);

My changes:

  • changed the"," in your for loop to ";"
  • updated "i += 1" to "i++"

Let me know if that doesn't solve your issue.

Hugo Paz
Hugo Paz
15,622 Points
Hugo Paz
Hugo Paz
15,622 Points

Hi Austinlilley,

removing the var is a really bad idea. Javascript will assume its a global variable and if you have the a variable with the same name somewhere else in your code, it can cause problems.

By declaring it inside the function with the keyword var, you ensure that its scope is limited to the function so if you have a global variable called i it will not be affected.

Austin Lilley
Austin Lilley
5,727 Points

Hugo Paz,

My mistake. I removed that bit of advice, thanks for catching that :)