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PHP Build a Simple PHP Application Working With Functions Introducing Functions

Evan Osczepinski
Evan Osczepinski
5,189 Points
Posted by Evan Osczepinski
Evan Osczepinski
5,189 Points

array_sum function challenge

I need some guidance please...

This is the question..

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.

<?php

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

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

echo $sum;

?>
Evan Osczepinski
Evan Osczepinski
5,189 Points
Evan Osczepinski
Evan Osczepinski
5,189 Points

This is what I did..

<?php

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

function array_sum($numbers); {

  return array_sum;

}


echo $numbers;

?>
Richard Duncan
Richard Duncan
5,568 Points
Richard Duncan
Richard Duncan
5,568 Points

Loads of errors in that code Evan Osczepinski you cannot redeclare a native function for one thing. The semi-colon after the function declaration and before the function body would also throw an error.

4 Answers

Richard Duncan
Richard Duncan
5,568 Points
Richard Duncan
Richard Duncan
5,568 Points

Have you re-watched the video? You might be looking at it too hard something simple such as: -

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

echo array_sum($numbers);

may provide the answer you're looking for.

Sam Bass
Sam Bass
9,038 Points
Sam Bass
Sam Bass
9,038 Points

Correct! this works! :) thanks!

Alan Mattanó
PLUS
Alan Mattanó
Courses Plus Student 12,188 Points
Alan Mattanó
Alan Mattanó
Courses Plus Student 12,188 Points

Uff i was making the function...

function array_sum($numbers) { foreach($numbers as $number) { $sum = $sum + $number; } return $sum; }

But wasn't necessary.

Evan Osczepinski
Evan Osczepinski
5,189 Points
Evan Osczepinski
Evan Osczepinski
5,189 Points

That was it. I guess I was over thinking that answers. Thanks a lot!

Evan Osczepinski
Evan Osczepinski
5,189 Points
Evan Osczepinski
Evan Osczepinski
5,189 Points

Okay so the semi colon is fixed, however what do I declare if not the native function in this case then? I have watched the video 4 times and cannot wrap my head around this.

Richard Duncan
Richard Duncan
5,568 Points
Richard Duncan
Richard Duncan
5,568 Points

You don't need to declare a native function as it is predefined. You just need to call it and pass the parameters of the arguments it expects. So in this example array_sum provides the sum value of all objects in the array. Call the function and pass $numbers as the parameter and it will provide the same result (14) as the foreach loop used in the example.