C++ Operator Precedence

Operator precedence determines the order in which operators are evaluated in an expression. Operators with higher precedence are evaluated before operators with lower precedence. If operators have the same precedence, associativity determines the order of evaluation.

Key Rules

Operators with higher precedence are executed first.
Associativity can be left-to-right or right-to-left depending on the operator.
Parentheses ( ) can be used to override default precedence and ensure the desired order of evaluation.

Common Operator Precedence in C++

Precedence	Operator(s)	Description	Associativity
1	() [] . ->	Parentheses, Array subscript, Member access	Left-to-right
2	! ~ ++ — + – * & sizeof	Unary operators, logical NOT, bitwise NOT, increment/decrement, unary plus/minus, dereference, address-of	Right-to-left
3	* / %	Multiplication, Division, Modulus	Left-to-right
4	+ –	Addition, Subtraction	Left-to-right
5	<< >>	Bitwise shift left and right	Left-to-right
6	< <= > >=	Relational operators	Left-to-right
7	== !=	Equality and inequality	Left-to-right
8	&	Bitwise AND	Left-to-right
9	^	Bitwise XOR	Left-to-right
10	\|	Bitwise OR	Left-to-right
11	&&	Logical AND	Left-to-right
12	\|\|	Logical OR	Left-to-right
13	= += -= *= /= %= <<= >>= &= ^= \|=	Assignment operators	Right-to-left
14	,	Comma operator	Left-to-right

Example Program

#include <iostream>
using namespace std;

int main() {
    int a = 5, b = 3, c = 2;
    int result;

    // Without parentheses
    result = a + b * c; // Multiplication (*) has higher precedence than addition (+)
    cout << "a + b * c = " << result << endl;

    // Using parentheses
    result = (a + b) * c; // Parentheses override precedence
    cout << "(a + b) * c = " << result << endl;

    return 0;
}

Output

a + b * c = 11
(a + b) * c = 16

Important Notes

Always use parentheses to make complex expressions clear and avoid mistakes.
Operator precedence rules are especially important when combining multiple types of operators.
Consult C++ documentation for full precedence tables if needed.

Next Topic

After mastering operators and precedence, you can move on to C++ Control Structures like if-else statements and loops.