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Operator precedence and associativity

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Operator precedence defines the order in which operators are evaluated in expressions with multiple operators.

Operators with higher precedence will be bound tighter (as if by parentheses) to its argument than the operators with lower precedence. For example, the expression a + b * c is equivalent to a + (b * c). That is, we firstly evaluate the multiplication operator and only then sum the result of the multiplication and the value of a. This is because the multiplication operator has higher precedence.

If there are multiple operators of the same precedence in the expression, the order of evaluation is defined by their associativity: either right-to-left or left-to-right. For example, a + b - c is equivalent to (a + b) - c as associativity of these particular operators is left to right.

The following table lists the precedence and associativity of C++ operators.

Operators are listed top to bottom, in descending precedence. in an

Precedence Operator Description Associativity
1 :: Scope resolution Left-to-right
2 ++ -- Suffix/postfix increment and decrement
() Function call
[] Array subscripting
. Element selection by reference
-> Element selection through pointer
3 ++ -- Prefix increment and decrement Right-to-left
+ Unary plus and minus
! ~ Logical NOT and bitwise NOT
(type) Type cast
* Indirection (dereference)
& Address-of
sizeof Size-of
new, new[] Dynamic memory allocation
delete, delete[] Dynamic memory deallocation
4 .* ->* Pointer to member Left-to-right
5 * / % Multiplication, division, and remainder
6 + Addition and subtraction
7 << >> Bitwise left shift and right shift
8 < <= For relational operators < and ≤ respectively
> >= For relational operators > and ≥ respectively
9 == != For relational = and ≠ respectively
10 & Bitwise AND
11 ^ Bitwise XOR (exclusive or)
12 | Bitwise OR (inclusive or)
13 && Logical AND
14 || Logical OR
15 ?: Ternary conditional Right-to-left
= Direct assignment (provided by default for C++ classes)
+= −= Assignment by sum and difference
*= /= %= Assignment by product, quotient, and remainder
<<= >>= Assignment by bitwise left shift and right shift
&= ^= |= Assignment by bitwise AND, XOR, and OR
16 throw Throw operator (for exceptions)
17 , Comma Left-to-right