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General Discussion

Posted by Don Shipley
Don Shipley
19,488 Points

PHP

Why does it reverse the numbers to 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;

?>

2 Answers

Aaron Graham
Aaron Graham
18,033 Points
Aaron Graham
Aaron Graham
18,033 Points

because of '$output = $number . $output'. Basically

  • the first iteration of the loop gives you '$output = $number' which is 1
  • the second iteration gives you '$output = $number . $output' which is 2 . 1 The new number is being concatenated to the front of your output buffer. You could change the order by making it '$output = $output . $number'
Jeffrey Wambugu
Jeffrey Wambugu
8,548 Points
Jeffrey Wambugu
Jeffrey Wambugu
8,548 Points

Hi, in the if statement, you are concatenating the first number behind the second one. that is when the first number (1) $output = 1; then concatenate the second (2) one after that so $output = 21; then concatenate the third(3) one after that so $output = 321;

If you want it to be 123 then use
$output = $output . $number;