# Learn Basic Algorithmic Thinking by Building a Number Sorter - Step 44

### Tell us what’s happening:

My code does not pass. I’m not sure what I’m doing wrong. It says “Your callback function should use an explicit return.” But I am using an explicit return (I think).

``````<!-- file: index.html -->

``````
``````/* file: styles.css */

``````
``````/* file: script.js */
// User Editable Region

const sortedValues = inputValues.sort((a, b) => {
if (a - b < 0) {
return a - b}
});

// User Editable Region
``````

User Agent is: `Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.15`

### Challenge Information:

Learn Basic Algorithmic Thinking by Building a Number Sorter - Step 44

You are using explicit return. The problem is with the logic of the callback function.

The callback function should return a number where:

• A negative value indicates that `a` should come before `b`.
• A positive value indicates that `a` should come after `b`.
• Zero or `NaN` indicates that `a` and `b` are considered equal.

Because of `if (a - b < 0)`, you are only returning a value when elements `a` and `b` are already in the correct order.

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