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Amy Hsieh
6,023 PointsRead these codes, my answer is 10 but it's wrong. Can anyone point out my mistake?
What does the following code display?
$numbers = array(1,2,3,4); $total = count($numbers); $sum = 0; $output = ""; $loop = 0;
foreach($numbers as $number) { $loop = $loop + 1; if ($loop < $total) { $output = $number . $output; } }
echo $output;
?>
1 Answer

Steven Parker
216,136 PointsSure, you were thinking that the numbers are being added, but "$output" is a string, and the period (".") is the string concatenation operator.
So that means the loop is creating a string by putting each digit in front of the others. Also notice that the loop count is incremented before the "if" is done, which will affect how many of the digits are handled.