C++ Operator Precedence

https://en.cppreference.com/w/cpp/language/operator_precedence

The following table lists the precedence and associativity of C++ operators. Operators are listed top to bottom, in descending precedence.

Precedence	Operator	Description	Associativity
1	::	Scope resolution	Left-to-right
2	a++   a--	Suffix/postfix increment and decrement
	type()   type{}	Functional cast
	a()	Function call
	a[]	Subscript
	.   ->	Member access
3	++a   --a	Prefix increment and decrement	Right-to-left
	+a   -a	Unary plus and minus
	!   ~	Logical NOT and bitwise NOT
	(type)	C-style cast
	*a	Indirection (dereference)
	&a	Address-of
	sizeof	Size-of[note 1]
	co_await	await-expression (C++20)
	new   new[]	Dynamic memory allocation
	delete   delete[]	Dynamic memory deallocation
4	.*   ->*	Pointer-to-member	Left-to-right
5	a*b   a/b   a%b	Multiplication, division, and remainder
6	a+b   a-b	Addition and subtraction
7	<<   >>	Bitwise left shift and right shift
8	<=>	Three-way comparison operator (since C++20)
9	<   <=	For relational operators < and ≤ respectively
	>   >=	For relational operators > and ≥ respectively
10	==   !=	For equality operators = and ≠ respectively
11	&	Bitwise AND
12	^	Bitwise XOR (exclusive or)
13	|	Bitwise OR (inclusive or)
14	&&	Logical AND
15	||	Logical OR
16	a?b:c	Ternary conditional[note 2]	Right-to-left
	throw	throw operator
	co_yield	yield-expression (C++20)
	=	Direct assignment (provided by default for C++ classes)
	+=   -=	Compound assignment by sum and difference
	*=   /=   %=	Compound assignment by product, quotient, and remainder
	<<=   >>=	Compound assignment by bitwise left shift and right shift
	&=   ^=   |=	Compound assignment by bitwise AND, XOR, and OR
17	,	Comma	Left-to-right

1. ↑ The operand of sizeof can't be a C-style type cast: the expression sizeof (int) * p is unambiguously interpreted as (sizeof(int)) * p, but not sizeof((int)*p).
2. ↑ The expression in the middle of the conditional operator (between ? and :) is parsed as if parenthesized: its precedence relative to ?: is ignored.

When parsing an expression, an operator which is listed on some row of the table above with a precedence will be bound tighter (as if by parentheses) to its arguments than any operator that is listed on a row further below it with a lower precedence. For example, the expressions std::cout << a & b and *p++ are parsed as (std::cout << a) & b and *(p++), and not as std::cout << (a & b) or (*p)++.

Operators that have the same precedence are bound to their arguments in the direction of their associativity. For example, the expression a = b = c is parsed as a = (b = c), and not as (a = b) = c because of right-to-left associativity of assignment, but a + b - c is parsed (a + b) - c and not a + (b - c) because of left-to-right associativity of addition and subtraction.

Associativity specification is redundant for unary operators and is only shown for completeness: unary prefix operators always associate right-to-left (delete ++*p is delete(++(*p))) and unary postfix operators always associate left-to-right (a[1][2]++ is ((a[1])[2])++). Note that the associativity is meaningful for member access operators, even though they are grouped with unary postfix operators: a.b++ is parsed (a.b)++ and not a.(b++).

Operator precedence is unaffected by operator overloading. For example, std::cout << a ? b : c; parses as (std::cout << a) ? b : c; because the precedence of arithmetic left shift is higher than the conditional operator.

Notes

Precedence and associativity are compile-time concepts and are independent from order of evaluation, which is a runtime concept.

The standard itself doesn't specify precedence levels. They are derived from the grammar.

const_cast, static_cast, dynamic_cast, reinterpret_cast, typeid, sizeof..., noexcept and alignof are not included since they are never ambiguous.

Some of the operators have alternate spellings (e.g., and for &&, or for ||, not for !, etc.).

In C, the ternary conditional operator has higher precedence than assignment operators. Therefore, the expression e = a < d ? a++ : a = d, which is parsed in C++ as e = ((a < d) ? (a++) : (a = d)), will fail to compile in C due to grammatical or semantic constraints in C. See the corresponding C page for details.

See also

Common operators
assignment	increment decrement	arithmetic	logical	comparison	member access	other
a = b a += b a -= b a *= b a /= b a %= b a &= b a |= b a ^= b a <<= b a >>= b	++a --a a++ a--	+a -a a + b a - b a * b a / b a % b ~a a & b a | b a ^ b a << b a >> b	!a a && b a || b	a == b a != b a < b a > b a <= b a >= b a <=> b	a[b] *a &a a->b a.b a->*b a.*b	a(...) a, b ? :
Special operators
static_cast converts one type to another related type  dynamic_cast converts within inheritance hierarchies  const_cast adds or removes cv qualifiers reinterpret_cast converts type to unrelated type C-style cast converts one type to another by a mix of static_cast, const_cast, and reinterpret_cast  new creates objects with dynamic storage duration delete destructs objects previously created by the new expression and releases obtained memory area sizeof queries the size of a type sizeof... queries the size of a parameter pack (since C++11) typeid queries the type information of a type noexcept checks if an expression can throw an exception (since C++11) alignof queries alignment requirements of a type (since C++11)