.. _arduino-increment:

++ (increment) / -- (decrement)
===============================

Description
-----------

Increment or decrement a variable



Syntax
------

::

    x++;  // increment x by one and returns the old value of x
    ++x;  // increment x by one and returns the new value of x
    
    x-- ;   // decrement x by one and returns the old value of x 
    --x ;   // decrement x by one and returns the new value of x  



Parameters
----------

x: an integer or long (possibly unsigned)



Returns
-------

The original or newly incremented / decremented value of the
variable.



Examples
--------

::

    x = 2;
    y = ++x;      // x now contains 3, y contains 3
    y = x--;      // x contains 2 again, y still contains 3 



See also
--------

`+= <http://arduino.cc/en/Reference/Arithmetic>`_
`-= <http://arduino.cc/en/Reference/Arithmetic>`_