Whether you are learning C++ or have been working with this programming language for a long time, C++ operators form the basis of effective programming. Although the meaning of some operators is intuitive, this is not the case for all.
What are C++ operators?
Basically, an operator is simply a character designating an operation. An operator can refer to one operand, but frequently it refers to several operands. Therefore, in most cases you get a new value. A popular example are arithmetic operators, for example “+” for adding and “-” for subtracting two numbers.
C++ operators are not only differentiated based on their function. THE operator status or affinity are also important criteria for differentiation:
| Continuity | Number of operands | Example |
|---|---|---|
| Unary operators | An operand | Logical negation: !var_name |
| Binary operators | Two operands | Addition : value1 + value2 |
| Ternary operators | Three operands | if-else condition: condition? condition_true : condition_false |
Carrier Priority
As with simple arithmetic operators or Python operators, there is also a prioritization of C++ operators. This indicates the order in which operators are parsed. For arithmetic operators, the known rules of dot before dash apply. However, there are also other rules you need to follow for other C++ operators.
if (var1 && var2 || var3) {
do_something();
}cpp
In the example above, the logical expression after the “if” operator is evaluated first. Here again, the “&&” (logical AND) operator takes precedence over the “|| » (logical OR). So, if the evaluation of “var1 && var2” or the evaluation of “var3” returns “true”, the function call of “do_something()” is executed.
If you want more certainty, you can also use parentheses.
Operator overloading in C++
You can overload most C++ operators. This means you can assign a new meaning to an existing operator in a context. To perform operator overloading in C++, you must use the keyword “operator “. Then you define the C++ operator you want to overload. Otherwise, operator overloading in C++ behaves like function overloading.
Overview of C++ Operators
Arithmetic operators
Some of the C++ arithmetic operators are already known from school. They work with numbers and then return a new number. With two exceptions (the pluses and minuses which we can think of as signs), the arithmetic operators are all binary operators.
| C++ operator | Meaning | Example |
|---|---|---|
+ |
Addition / unary plus | 6 + 4 |
- |
Subtraction / unary minus | 10 - 6 |
* |
Multiplication | 10 * 3 |
/ |
Division | 20 / 10 |
% |
Modulo | 21 % 2 |
Assignment operators
As in most programming languages, values are stored in variables in C++. To assign specific values to such variables, you need special operators.
Simple assignment operators
| C++ operator | Meaning | Example |
|---|---|---|
= |
Simple assignment | x = 3 |
++ |
Increment | x++ |
– |
Decrement | x– |
Compound assignment operators
In addition to simple assignment operators, C++ also supports compound operators. These are arithmetic or “bitwise” operations connected simultaneously with a value assignment :
In the sample code above, the variable “x” is given a numeric value of 4 based on a simple assignment. The compound assignment operator “+=” is then used to perform an arithmetic addition and store the resulting value directly in “x”. The assignment looks like this: “x = x + 2”.
| C++ operator | Meaning | Example |
|---|---|---|
+= |
Sum and allocation | x += 2 |
-= |
Subtraction and assignment | x -= 2 |
*= |
Multiplication and assignment | x *= 2 |
/= |
Division and assignment | x /= 2 |
%= |
Modulo and assignment | x % = 2 |
&= |
Bitwise AND operator and assignment | b &= 1 |
<<= |
Rotate left and assign | b <<= 1 |
>>= |
Rotate right and assign | b >>= 1 |
^= |
Bitwise OR operator and assignment | b ^= 1 |
| ` | =` | Bitwise OR operator and assignment |
C++ Logical Operators
You can use C++ logical operators to make comparisons of two expressions. With the exception of “non-logical” expression, which always refers to a single instruction and overrides its true value, logical operators are binary.
| C++ operator | Meaning | Example |
|---|---|---|
&& |
AND logical | true && true |
| ` | ` | |
! |
NOT logical | !true |
Comparison operators
Comparison operators are C++ operators that examine the relationship between two elements; they are therefore binary. Except for the three-way comparison which returns a number, the value returned by all C++ comparison operators is a true value.
| C++ operator | Meaning | Example |
|---|---|---|
== |
Equality | a == b |
!= |
Inequality | a != b |
<= |
Less than or equal to | a <= b |
>= |
Greater than or equal to | a >= b |
< |
Smaller than | a < b |
> |
Bigger than | a > b |
<=> |
Three-way comparison | a <=> b |
Bit manipulation
To be able to access individual bits efficiently and improve the speed of programs, there are C++ bit operators that are particularly important for performance-oriented programming.
| C++ operator | Meaning | Example |
|---|---|---|
& |
AND bit operator | a & b |
| ` | ` | OR bit operator |
^ |
Exclusive OR bit operator | a ^ b |
~ |
1’s complement operator | ~a |
<< |
Left Shift Operators | a << b |
>> |
Right Shift Operators | a >> b |
Storage management
C++ is a machine language and therefore offers a number of operators to help you manage memory.
| C++ operator | Meaning | Example |
|---|---|---|
& |
Determine the address | & x |
sizeof() |
Determines the memory requirements of an expression | sizeof(x) |
new |
Creates a new object and returns pointers | object* pointer = new object() |
delete |
Delete an object | delete object |
Data access for objects and pointers
The following C++ operators will help you if you want to access individual members of objects or pointer storage areas.
| C++ operator | Meaning | Example |
|---|---|---|
* |
Indirection operator | *pointer = 3; |
. |
Member Access Operators | object.member = 2; |
-> |
Member access operators with a pointer | objectpointer-> member = 2 ; |
