How to swap numbers in PHP

 Swap two number using third variable program in PHP

<?php
$a=10;
$b=20;
echo "Value of a: $a</br>";
echo "Value of b: $b</br>";        $temp=$a;
$a=$b;
$b=$temp;
echo "Value of a: $a</br>";
echo "Value of b: $b</br>";
?>

Output:
Value of a: 10
Value of b: 20
Value of a: 20
Value of b: 10