# Learn Basic Algorithmic Thinking by Building a Number Sorter - Step 15

### Tell us what’s happening:

Instructions state: “Because you need to compare elements, you’ll need to use a nested `for` loop. This loop should iterate through every element in the array except the last one. Use `j` as your inner loop’s iterator variable.”

With the following code, I’m getting the error message " Your inner `for` loop should iterate through every element in the array except the last one."

I’m very confused because from what I understand, the code I’ve written should do exactly that: increment j until array.length - 1, i.e. every element in the array except the last element in the array. I don’t get it.

### Your code so far

WARNING

The challenge seed code and/or your solution exceeded the maximum length we can port over from the challenge.

You will need to take an additional step here so the code you wrote presents in an easy to read format.

Please copy/paste all the editor code showing in the challenge from where you just linked.

``````const bubbleSort = (array) => {
for (let i = 0; i < array.length; i++) {
for (let j = 0; j < (array.length - 1); j++) {}
}
}
``````

### Your browser information:

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36`

### Challenge Information:

Learn Basic Algorithmic Thinking by Building a Number Sorter - Step 15

This looks right to me too. Try it without the parentheses in your compare argument. I think this is a case of the tests not accounting for valid variations in code.

1 Like

Wow, that worked. Unbelievable!