**Tell us what’s happening:**

I know the Problem but what is problem with my code is it right or it’s wrong Please explain me.

after concating the array my result is `[ 5, 6, 3, 2, 9, 5, 6, 3, 2, 9 ]`

after the sort the array `[ 2, 2, 3, 3, 5, 5, 6, 6, 9, 9 ]`

what exactly do the code

**Your code so far**

```
var globalArray = [5, 6, 3, 2, 9];
function nonMutatingSort(arr) {
// Add your code below this line
let t = arr.concat(globalArray);
return t.sort((a,b) => a - b);
}
// Add your code above this line
nonMutatingSort(globalArray);
```

**Your browser information:**

User Agent is: `Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.84 Safari/537.36`

.

**Link to the challenge:**

https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/functional-programming/return-a-sorted-array-without-changing-the-original-array