Value of $a is :10
After Pre-increment value of $a ( i.e. ++$a ) is: 11
Value of $a is :20
After Post-increment value of $a ( i.e. $a++ ) is: 20
Value of $a is :30
After Pre-decrement value of $a ( i.e. --$a ) is: 29
Value of $a is :40
After Post-decrement value of $a ( i.e. $a-- ) is: 40