C、C++运算符优先级列表

1.C语言运算符优先级

运算符按照优先级大小由上向下排列，在同一行的运算符具有相同优先级。第二行是所有的一元运算符。
 

运算符解释结合方式() [] -> .括号（函数等），数组，两种结构成员访问由左向右! ~ ++ -- + - 

* & (类型) sizeof

否定，按位否定，增量，减量，正负号，

间接，取地址，类型转换，求大小

由右向左* / %乘，除，取模由左向右+ -加，减由左向右<< >>左移，右移由左向右< <= >= >小于，小于等于，大于等于，大于由左向右== !=等于，不等于由左向右&按位与由左向右^按位异或由左向右|按位或由左向右&&逻辑与由左向右||逻辑或由左向右? :条件由右向左= += -= *= /= 

&= ^= |= <<= >>=

各种赋值由右向左,逗号（顺序）由左向右

 

2.C++运算符优先级

PrecedenceOperatorDescriptionExampleAssociativity1()
[]
->
.
::
++
--Grouping operator
Array access
Member access from a pointer
Member access from an object
Scoping operator
Post-increment
Post-decrement(a + b) / 4;
array[4] = 2;
ptr->age = 34;
obj.age = 34;
Class::age = 2;
for( i = 0; i < 10; i++ ) ...
for( i = 10; i > 0; i-- ) ...left to right2!
~
++
--
-
+
*
&
(type)
sizeofLogical negation
Bitwise complement
Pre-increment
Pre-decrement
Unary minus
Unary plus
Dereference
Address of
Cast to a given type
Return size in bytesif( !done ) ...
flags = ~flags;
for( i = 0; i < 10; ++i ) ...
for( i = 10; i > 0; --i ) ...
int i = -1;
int i = +1;
data = *ptr;
address = &obj;
int i = (int) floatNum;
int size = sizeof(floatNum);right to left3->*
.*Member pointer selector
Member pointer selectorptr->*var = 24;
obj.*var = 24;left to right4*
/
%Multiplication
Division
Modulusint i = 2 * 4;
float f = 10 / 3;
int rem = 4 % 3;left to right5+
-Addition
Subtractionint i = 2 + 3;
int i = 5 - 1;left to right6<<
>>Bitwise shift left
Bitwise shift rightint flags = 33 << 1;
int flags = 33 >> 1;left to right7<
<=
>
>=Comparison less-than
Comparison less-than-or-equal-to
Comparison greater-than
Comparison geater-than-or-equal-toif( i < 42 ) ...
if( i <= 42 ) ...
if( i > 42 ) ...
if( i >= 42 ) ...left to right8==
!=Comparison equal-to
Comparison not-equal-toif( i == 42 ) ...
if( i != 42 ) ...left to right9&Bitwise ANDflags = flags & 42;left to right10^Bitwise exclusive ORflags = flags ^ 42;left to right11|Bitwise inclusive (normal) ORflags = flags | 42;left to right12&&Logical ANDif( conditionA && conditionB ) ...left to right13||Logical ORif( conditionA || conditionB ) ...left to right14? :Ternary conditional (if-then-else)int i = (a > b) ? a : b;right to left15=
+=
-=
*=
/=
%=
&=
^=
|=
<<=
>>=Assignment operator
Increment and assign
Decrement and assign
Multiply and assign
Divide and assign
Modulo and assign
Bitwise AND and assign
Bitwise exclusive OR and assign
Bitwise inclusive (normal) OR and assign
Bitwise shift left and assign
Bitwise shift right and assignint a = b;
a += 3;
b -= 4;
a *= 5;
a /= 2;
a %= 3;
flags &= new_flags;
flags ^= new_flags;
flags |= new_flags;
flags <<= 2;
flags >>= 2;right to left16,Sequential uation operatorfor( i = 0, j = 0; i < 10; i++, j++ ) ...left to right

例如：C++中

1）y=*px++ 相当于y=*(px++) (++优先级高)

2）&ptr->a等于&(ptr->a)而不是等于(&ptr)->a

3）逻辑运算符的优先级： ！(非) >   &&(与)   >   ||(或)

4）关系运算符优先级

      <     <=       >       >=                       ==    !=

       优先级相同（高）            优先级相同（低）

5)  条件运算符优级高于赋值运算符，低于逻辑运算符   x=a>b?a:b;

6）有10种复合运算符：+=, -=, *=, /=, %=,<<=,>>=,&=,^=,|=