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PHP

Posted by Lucas Santos
Lucas Santos
19,315 Points

What does the following code display?

<?php

$numbers = array(1,2,3,4);

$total = count($numbers);

$sum = 0;

$output = "";

$i = 0;

foreach($numbers as $number) {

    $i = $i + 1;

    if ($i < $total) {

        $sum = $sum + $number;

    }

}

echo $sum;

?>

Choices: 10 - 6 - 1 - 123

My guess was 10 because they are adding $sum plus the $number instead of concatenating with the $output but I was wrong.

1 Answer

Erin Olmon
Erin Olmon
2,271 Points

I'm going with 6 because on the final iteration $i=4 and $total=4. In order for the summation step to occur, $i must be less than $total but in the final iteration it's equal, so the code will not do the final addition.

Lucas Santos
Lucas Santos
19,315 Points

So how did you come up with 6?

Chris Shaw
Chris Shaw
26,676 Points

See the below

1 + 0 = 1 // $sum = 1
1 + 2 = 2 // $sum = 3
3 + 3 = 6 // $sum = 6

Because $i is incrementing by one number more every time the value of $i will be equal to 4 before the 4th index within the $numbers array is called.

Lucas Santos
Lucas Santos
19,315 Points

ooohhhh I see ok so the value of $sum stores a new value for each time $i increments by 1 and adding that to each number in the array before it get's to 4