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\\Here is simplest php function example
<?php
function swap($a,$b){
print nl2br("Before swapping\n");
print nl2br("a = $a and b = $b \n\n\n");
$a = $a + $b; // 30 = 10 + 20
$b = $a - $b;
$a = $a - $b;
print nl2br("After swapping\n");
print nl2br("a = $a and b = $b \n");
}
swap(10,20);
?>
