**Tell us what’s happening:**

Describe your issue in detail here.

I feel like i somewhat conceptually understand recursion. But in this problem why are we adding " arr[n - 1]" se seen below.

return sum(arr, n - 1) + arr[n - 1];

it makes more sense to me to say " + arr [n];

```
**Your code so far**
```

```
function sum(arr, n) {
// Only change code below this line
function sum(arr, n) {
if(n <= 0) {
return 0;
} else {
return sum(arr, n - 1) + arr[n - 1];
}
}
// Only change code above this line
}
```

```
**Your browser information:**
```

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.63 Safari/537.36`

**Challenge:** Replace Loops using Recursion

**Link to the challenge:**