The unary operators take a single argument in C++ language. Some of the operators you have already seen in previous articles are unary operators.
Here is the list of unary operators.
| Unary Operators | Description |
| * | Dereference operator |
| & | Address Of operator |
| Minus sign | |
| ! | Not operator |
| ~ | Complement |
| ++ | Increment operator |
| — | Decrement operator |
| type | Forced type conversion |
| sizeof | Size of the data type |
Contents
Dereference Operator (*)
When a C++ pointer type is declared and it is pointing to a variable. The dereference operator helps to access the content of a pointer type.
We will learn more about while discussing pointers.
Address Of Operator(&)
It resembles the bitwise AND, but when used as a unary operator it returns the address of the variable.
int A = &B;
The variable A will store address of the variable B, not its value.
Minus Sign(-)
Minus is an arithmetic operator, but as a unary operator, it is used to denote a negative value. It is most commonly used the unary operator in C++ programs.
Negation Operator(!)
The negation is a logical operator which negates the value of a boolean variable. If the value is 1 (true) then, it becomes 0 (false). If the value is 0 (false) then, it becomes 1 (true).
Bitwise Complement (~)
The bitwise complement modifies the binary value of a variable to 2’s complement binary value. In other words, you get a negative value for a positive number plus 1.
p = 45 becomes -46 after ~p.
Increment Operator (++)
The increment operator is used in loop structures. You will learn about loop structures later in this C++ tutorial. The increment operator increment an associated variable by 1.
i = 12;
i++; // same as saying i = i + 1;
The value of i after increment is 13.
Decrement Operator ()
The decrement operator decreases the associated variable value by 1.
i = 34;
i;
The value will be 33 after decrement.
Type Operator
The type conversion operator is used to modify the data type of a variable by force. The initial data type is changed to what specified in the type operator. It is also known as cast operator.
int A;
A = 10;
(float) A;
This will change the variable A into floating type from an integer.
Sizeof Operator( sizeof)
The sizeof operator is a special operator that returns the size of the data type in C++ program.
int A;
sizeof(A);
This will return the size of integer data type which is 4 bytes.