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C Operator Precedence and   Associativity

What do you mean by Operator Precedence?

Operator precedence is used to determine the order of operators evaluated in an expression. In c programming language every operator has precedence (priority). When there is more than one operator in an expression the operator with higher precedence is evaluated first and the operator with least precedence is evaluated last.

What is Operator Associativity?

Operator associativity is used to determine the order of operators with equal precedence evaluated in an expression. In c programming language, when an expression contains multiple operators with equal precedence, we use associativity to determine the order of evaluation of those operators.

In c programming language the operator precedence and associativity is as shown in the following table…

PrecedenceOperatorOperator MeaningAssociativity
1()
[]
->
.
function call
array reference
structure member access
structure member access
Left to Right
2!
~
+

++

&
*
sizeof
(type)
negation
1’s complement
Unary plus
Unary minus
increment operator
decrement operator
pointer
returns size of a variable
type conversion
Right to Left
3*
/
%
multiplication
division
remainder
Left to Right
4+
subtraction
Left to Right
5<<
>>
left shift
right shift
Left to Right
6<
<=
>
>=
less than
less than or equal to
greater than
greater than or equal to
Left to Right
7==
!=
equal to
not equal to
Left to Right
8&bitwise ANDLeft to Right
9^bitwise EXCLUSIVE ORLeft to Right
10|bitwise ORLeft to Right
11&&logical ANDLeft to Right
12||logical ORLeft to Right
13?:conditional operatorLeft to Right
14=
*=
/=
%=
+=
-=
&=
^=
|=
<<=
>>=
assignment
assign multiplication
assign division
assign remainder
assign subtraction
assign bitwise AND
assign bitwise XOR
assign bitwise OR
assign left shift
assign right shift
Right to Left
15,separatorLeft to Right

Key features   in the above table are:-

The operator precedence decreases from top to bottom.

&

It increases from bottom to top.