Php Operator

Arithmetic Operators

Arithmetic operators work with numeric values to perform common arithmetical operations.

<?php
$num1=8;
$num2=6;
//Addition
echo $num1+$num2; //14
//Substraction
echo $num1-$num2; //2
//Multiplication
echo $num1*$num2; //48

//Division
echo $num1/$num2 ; //1.33333333


?>

Modulus

The modulus operator, represented by the % sign, returns the remainder of the division of the first operand by the second operand:

<?php
$x=14;
$y=3;
echo $x%$y //2

?>

Increment & Decrement

The increment operators are used to increment a variable's value.
The decrement operators are used to decrement a variable's value.

<?php
$x++; // equivalent to $x = $x+1;

$x--; // equivalent to $x = $x-1;
?>

Increment and decrement operators either precede or follow a variable.

<?php
$x++; // post-increment 

$x--; // post-decrement 
++$x; // pre-increment 
--$x; // pre-decrement
?>

The difference is that the post-increment returns the original value before it changes the variable, while the pre-increment changes the variable first and then returns the value.

Example:

<?php
$a  = 2; $b = $a++; // $a=3,  $b=2

$a  = 2; $b = ++$a; // $a=3,  $b=3
?>