"Note" C operator precedence formula easy wrong point

C-Operator Precedence!

Priority level	Operator	Name or meaning	Use form	Combination direction	Description
1	[]	Array subscript	array name [constant expression]	Left to right
	()	Parentheses	(expression)/function name (formal parameter list)
	.	Member selection (object)	Object. Member name
	-	Member selection (pointer)	Object pointers, member names
2	-	Minus sign operator	-expression	Right to Left	Monocular operator
	Type	Forcing type conversions	(data type) expression
	++	Self-increment operator	+ + variable name/variable name + +		Monocular operator
	--	Self-decrement operator	--Variable name/variable name--		Monocular operator
	*	Value operator	* Pointer variable		Monocular operator
	&	Fetch address operator	& Variable Name		Monocular operator
	!	Logical non-operator	! An expression		Monocular operator
	~	Bitwise inverse operator	~ Expression		Monocular operator
	sizeof	Length operator	sizeof (expression)
3	/	Except	An expression/expression	Left to right	Binocular operator
	*	By	Expression-expression *		Binocular operator
	%	Remainder (modulo)	Integer expression/integer expression		Binocular operator
4	+	Add	An expression + an expression	Left to right	Binocular operator
	-	Reducing	Expression-expression		Binocular operator
5	<<	Move left	Variables << expressions	Left to right	Binocular operator
	>>	Move right	Variables >> expressions		Binocular operator
6	>	Greater than	Expressions > expressions	Left to right	Binocular operator
	>=	Greater than or equal	Expression->= expression		Binocular operator
	<	Less than	Expressions < expressions		Binocular operator
	<=	Less than or equal	Expression-<= expression		Binocular operator
7	==	Equals	Expression-= = Expression	Left to right	Binocular operator
	!=	Not equal to	Expression! = Expression		Binocular operator
8	&	Bitwise-AND	Expressions & Expressions	Left to right	Binocular operator
9	^	Bitwise XOR OR	An expression ^ expression	Left to right	Binocular operator
10	|	Bitwise OR	Expression-expression	Left to right	Binocular operator
11	&&	Logic and	Expressions && Expressions	Left to right	Binocular operator
12	||	Logical OR	An expression | | An expression	Left to right	Binocular operator
13	?:	Conditional operators	Expression 1? Expression 2: Expression 3	Right to Left	Trinocular operator
14	=	Assignment operators	variable = expression	Right to Left
	/=	Assign value after addition	Variable-/= expression
	*=	Multiply post-Assign value	Variable-*= expression
	%=	Assign value after modulo	Variable-%= expression
	+=	Add after Assignment	Variable + = expression
	-=	Reduced-value Assignment	Variable-= expression
	<<=	Assign value after left shift	Variable-<<= expression
	>>=	Assign value after right shift	Variable->>= expression
	&=	Bitwise AND post-assigned values	Variable-&= expression
	^=	Bitwise XOR or post-assignment	Variable-^= expression
	|=	Bitwise OR post-assigned value	Variable-|= expression
15	,	Comma operator	An expression, an expression, a...	Left to right	Left-to-right sequential operation
Description
Operators of the same precedence, with the order of operations determined by the binding direction

Some error-prone priority issues

In the table above, how do you prioritize an expression if there are several operators with Priority 1? This is a confusing place for many beginners. These error-prone situations are sorted out in the following table:

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Priority formula

parenthesis member first; parentheses operator [] () member operator. -

All monocular second; All monocular operators such as + + + (positive)-(negative) pointer operation *&

Multiplication Yozo, plus minus four; this "remainder" means the residual operation is%

Shift five, relationship six, shift operator:<< >>, relationship:> < >= <=, etc.

Equals (and) unequal row seventh; = = = = =

Bits and Xor and bits or; these are bitwise operations: Bits and (&) XOR (^) bits or (|)

"Three points of the world" eighty or ninety;

logical or heel; logical Operator: | | and &&

12 and 11; Note order: Priority (| |) Bottom-to-priority (&&)

The condition is higher than the assignment, the three-mesh operator precedence is ranked to 13-bit only than the assignment operator and the "," high

Lowest comma operation level! The comma operator has the lowest precedence

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"Note" C operator precedence formula easy wrong point