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Start your free trial###### Tony McCabe

8,445 Points# Introduction User-Defined Function 3of 3

It looks like you have not created a variable named $sum in your main code, outside of the function. Please create it and store the return value from the mimic_array_sum function call in it.<?php

function mimic_array_sum($sum) { $sum = 0;

```
foreach($array as $element) {
$sum = $sum + $element;
}
return $sum;
```

}

$palindromic_primes = array(11, 757, 16361);

?>

## 11 Answers

###### Randy Hoyt

Treehouse Guest TeacherWell, I do have all the answers here in my top-secret briefcase. :-)

```
____
.---[[__]]----.
;-------------.|
| ||
| ||
| ||
|_____________|/
```

###### Tony McCabe

8,445 PointsBummer!It looks like you have not created a variable named $sum in your main code, outside of the function. Please create it and store the return value from the mimic_array_sum function call in it. where do you place the variable?

###### Randy Hoyt

Treehouse Guest TeacherYour function code looks right. Now you need to create a variable *outside* of the function, like this:

```
function mimic_array_sum($sum) {
$sum = 0;
foreach($array as $element) {
$sum = $sum + $element;
}
return $sum;
}
$palindromic_primes = array(11, 757, 16361);
$sum = ____;
```

###### Tony McCabe

8,445 Points$sum = 17118; $sum = 0; $sum = return; Which one or do I need to go back to math class

###### Randy Hoyt

Treehouse Guest TeacherThe instructions ask you to do this:

Please create it and store the return value from the mimic_array_sum function call in it.

That means do this:

```
$sum = mimic_array_sum($palindromic_primes);
```

In earlier step, we wrote the `mimic_array_sum`

function that receives an array of numbers and adds up all its elements. In this step, we need to *call* that function. We pass in an array of numbers (`$palindromic_primes`

), and the function returns the sum of them. We then load that return value into a variable named `$sum`

.

Does that help?

###### Tony McCabe

8,445 Points<?php

function mimic_array_sum($array) {
$sum $sum;

foreach($array as $element) {
$sum = $sum + $element;
}
return $sum;
}

$palindromic_primes = array(11, 757, 16361);

$sum = mimic_array_sum($palindromic_primes); ?> "Still say's bummer!

###### Randy Hoyt

Treehouse Guest Teacher"Bummer" means you have invalid PHP code. You changed a line from what you sent me earlier. You now have this ...

```
<?php
function mimic_array_sum($array) {
$sum $sum;
```

... but you used to have this:

```
<?php
function mimic_array_sum($array) {
$sum = 0;
```

It was correct before, and you'll need to change it back.

###### Tony McCabe

8,445 PointsIt looks like you are not displaying anything to the screen. Be sure to use an echo command.

function mimic_array_sum($array) { $sum = 0; I tried: echo sum = 0 echo 0;

###### Randy Hoyt

Treehouse Guest TeacherTry this:

```
echo $sum;
```

###### Randy Hoyt

Treehouse Guest TeacherOh, but not inside the function. You need to do that at the end of your code.

```
$sum = mimic_array_sum($palindromic_primes);
echo $sum;
```

###### Tony McCabe

8,445 Pointsperfect your a genius!!