Precedence
In the following table, operators grouped together in a row have the same precedence. For example, the first four entries in this table (), [], ., and -> all share the same precedence. These four operators follow the rule of Left-to-Right associativity which is used as a tie breaker when two or more of these appear in the same expression. The next group of operators starting with + and ending with (type) all share the next level of precedence.
Operator Description Associativity
( )
[ ]
.
->
Parenthesized Expression
Array Subscript
Structure Member
Structure Pointer
Left - to - Right
+ -
++ - -
! ~
*
&
sizeof
(type)
Unary + and - (Postitive and Negative Signs)
Increment and Decrement
Logical NOT and Bitwise Complement
Dereference (Pointer)
Size of Expression or Type
Explicit Typecast
Right - to - Left
* / % Multiply, Divide, and Modulus Left - to - Right
+ - Add and Subtract Left - to - Right
« » Shift Left and Shift Right Left - to - Right
< <=
> >=
Less Than and Less Than or Equal To
Greater Than and Greater Than or Equal To
Left - to - Right
== != Equal To and Not Equal To Left - to - Right
& Bitwise AND Left - to - Right
^ Bitwise XOR Left - to - Right
| Bitwise OR Left - to - Right
&& Logical AND Left - to - Right
|| Logical OR Left - to - Right
?: Conditional Operator Right - to - Left
=
+= -=
/= *=
%=
«= »=
&= |=
^=
Assignment
Addition and Subtraction Assignments
Division and Multiplication Assignments
Modulus Assignment
Shift Left and Shift Right Assignments
Bitwise AND and OR Assignements
Bitwise XOR Assignment
Right - to - Left
, Comma Operator Left - to - Right
When expressions contain multiple operators, their precedence determines the order of evaluation
Expression Effective Expression
a - b * c a - (b * c)
a + ++b a + (++b)
a + ++b * c a + ((++b)*c)

If functions are used in an expression, there is no set order of evaluation for the functions themselves.
e.g. x = f() + g()
There is no way to know if f() or g() will be evaluated first.

## Associativity

If two operators have the same precedence, their associativity determines the order of evaluation.
Expression Associativity Effective Expression
x / y % z Left - to - Right (x / y) % z
x = y = z Right - to - Left x = (y = z)
~++x Right - to - Left ~(++x)

You can rely on these rules, but it is good programming practice to explicitly group elements of an expression by using parentheses.

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