C++ Operator Precedence

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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 ≤ and > and ≥ respectively
10 ==   != For equality operators = and ≠ respectively
11 a&b 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.

[edit] 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.

[edit] See also

Common operators
assignment increment
arithmetic logical comparison member

a = b
a += b
a -= b
a *= b
a /= b
a %= b
a &= b
a |= b
a ^= b
a <<= b
a >>= b


a + b
a - b
a * b
a / b
a % b
a & b
a | b
a ^ b
a << b
a >> b

a && b
a || b

a == b
a != b
a < b
a > b
a <= b
a >= b
a <=> b


function call
a, b
a ? b : c
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)

C documentation for C operator precedence