分类： C/C++
2009-12-24 10:49:43
| Precedence | Operator | Description | Example | Associativity |
|---|---|---|---|---|
| 1单运算符 | () [] -> . :: ++ -- |
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 right |
| 2单运算符 | ! ~ ++ -- - + * & (type) |
Logical negation Bitwise complement Pre-increment Pre-decrement Unary minus Unary plus Dereference Address of Cast to a given type Return size in bytes |
if( !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 left |
| 3 | ->* .* |
Member pointer selector Member pointer selector |
ptr->*var = 24; obj.*var = 24; |
left to right |
| 4算术 | * / % |
Multiplication Division Modulus |
int i = 2 * 4; float f = 10 / 3; int rem = 4 % 3; |
left to right |
| 5算术 | + - |
Addition Subtraction |
int i = 2 + 3; int i = 5 - 1; |
left to right |
| 6位移 | << >> |
Bitwise shift left Bitwise shift right |
int flags = 33 << 1; int flags = 33 >> 1; |
left to right |
| 7比较 | < <= > >= |
Comparison less-than Comparison less-than-or-equal-to Comparison greater-than Comparison geater-than-or-equal-to |
if( i < 42 ) ... if( i <= 42 ) ... if( i > 42 ) ... if( i >= 42 ) ... |
left to right |
| 8比较 | == != |
Comparison equal-to Comparison not-equal-to |
if( i == 42 ) ... if( i != 42 ) ... |
left to right |
| 9位运算 | & | Bitwise AND | flags = flags & 42; | left to right |
| 10位运算 | ^ | Bitwise exclusive OR | flags = flags ^ 42; | left to right |
| 11位运算 | | | Bitwise inclusive (normal) OR | flags = flags | 42; | left to right |
| 12位运算 | && | Logical AND | if( conditionA && conditionB ) ... | left to right |
| 13逻辑 | || | Logical OR | if( conditionA || conditionB ) ... | left to right |
| 14逻辑 | ? : | Ternary conditional (if-then-else) | int i = (a > b) ? a : b; | right to left |
| 15赋值 | = += -= *= /= %= &= ^= |= <<= >>= |
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 assign |
int 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 left |
| 16 | , | Sequential evaluation operator | for( i = 0, j = 0; i < 10; i++, j++ ) ... | left to right |
