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PHP Build a Simple PHP Application Working With Functions Introducing Functions

Juliette Tworsey
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Juliette Tworsey
Front End Web Development Techdegree Graduate 32,425 Points
Posted by Juliette Tworsey
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Juliette Tworsey
Front End Web Development Techdegree Graduate 32,425 Points

Stage 6- Working with functions

"The code below creates an array of numbers, loops through them one at a time, and sums their values. PHP actually has a native function that does this same thing: array_sum(). [The array_sum() function receives an array as its one and only argument, and it sends back the sum as the return value.] Modify the code below: remove the foreach loop and the working sum variable, replacing them with a call to the array_sum() function instead."

Anyone have any idea on how to approach this? I didn't find the preceding video to be of much guidance here. Thanks-

sum.php 
<?php

$numbers = array(1,5,8);

echo "sum(numbers) = " . array_sum($numbers) . "\n";


?>

1 Answer

Joe Cochran
Joe Cochran
18,249 Points

This is a case where the challenge engine is being really picky. The challenge asks you to replace the loop with the array_sum() function. We start with:

<?php

$numbers = array(1,5,8);

$sum = 0;
foreach($numbers as $number) {
    $sum = $sum + $number;
}

echo $sum;

?>

Then, as instructed, I will remove the loop entirely.

<?php

$numbers = array(1,5,8);

$sum = 0;

echo $sum;

?>

With this code, the easiest way to accomplish the task is to replace $sum = 0; with array_sum(). I'll go ahead and add $sum = array_sum($numbers):

<?php

$numbers = array(1,5,8);

$sum = array_sum($numbers);

echo $sum;

?>

The good news is you were using the function correctly! Unfortunately, the challenge engine is checking the value of $sum at the end, whereas you were outputting the result of the array_sum() function directly.