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PHP Build a Simple PHP Application Working With Functions Working with Functions

Posted by Chloe Conn
Chloe Conn
3,217 Points

WHY!!

Why is the output to this 321?

<?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) {

    $output = $number . $output;

}

}

echo $output;

?>

3 Answers

Hayden Taylor
Hayden Taylor
5,076 Points
Hayden Taylor
Hayden Taylor
5,076 Points

the answer is 321 because output is treating it like a string. you are not adding the numbers like in the other quiz questions.

So what it is really doing is output = "3" . "2" . "1" where dot indicates a string concatenation.

Chloe Conn
Chloe Conn
3,217 Points
Chloe Conn
Chloe Conn
3,217 Points

why does it start with the number three and not one?

Hayden Taylor
Hayden Taylor
5,076 Points
Hayden Taylor
Hayden Taylor
5,076 Points

because you are always adding output to the end of the new string.

So first loop iteration is

Output = "1" . "" (output at the end of the string is empty because nothing is in it yet right?)

2) output = "2" . output (which is 1 from the previous iteration)

3) output = "3" . output (which is 2 1)

So again

1) output = 1 + "" 2) output = 2 + "1" 3) output = 3 + "21"

Hope this explains it better post a comment back if you are still having trouble.

Chloe Conn
Chloe Conn
3,217 Points
Chloe Conn
Chloe Conn
3,217 Points

Yes thank you so much!!! I understand now