Swapping Algorithm without extra variable.

One way to this is by using the Exclusive OR (XOR)

Sample Code

$x = $x ^ $y;
$y = $y ^ $x;
$x = $x ^ $y;

Explanation

Lets try to use X=5 and Y=15; Now let convert the value of X and Y to each Binary data. Here's is, X=0101 and Y=1111

• Lets see first statement.
  
  $x = $x ^ $y; Binary: 1010 ^ 1111 ------ 0101 ( X now has value of 10)
• Second Statement
• Last statement