A simple example of C ++ overload Operators

A simple example of C ++ overload Operators

We can redefine or reload most of the built-in operators in C ++. In this way, you can use custom operators.

The overloaded operator is a function with a special name. The function name is composed of the operator keyword and the operator symbol to be reloaded. Like other functions, the overload operator has a return type and a parameter list.
Box operator + (const Box &);

The Declaration addition operator is used to add two Box objects and return the final Box object. Most overload operators can be defined as common non-member functions or class member functions. If we define the above function as a non-member function of the class, we need to pass two parameters for each operation, as shown below:
Box operator + (const Box &, const Box &);

The following example uses a member function to demonstrate the concept of operator overloading. As follows:

# Include <iostream>

Using namespace std;

Class Person {
Public:
Person (int num): age (num ){}

/* Class member functions */
Int operator + (const Person & temp ){
Return (this-> age + temp. age );
}

Int age;
};

/* Non-class member functions */
Int operator-(const Person & a, const Person & B ){
Return (a. age-b.age );
}

Int main ()
{
Person John (20), Tom (18 );

Cout <John + Tom <endl;
Cout <John-Tom <endl;

Return 0;
}

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Reload operators/non-overload Operators

The following is a list of operators that can be reloaded:

Category	Symbol
Binary Arithmetic Operators	+ (Plus),-(minus), * (multiplication),/(Division), % (Modulo)
Relational operators	= (Equal ),! = (Not equal to), <(less than),> (greater than>, <= (less than or equal to), >=( greater than or equal)
Logical operators	(Logical or), & (logical and ),! (Non-logical)
Single Object Operator	+ (Positive),-(negative), * (pointer), & (obtain address)
Auto-incrementing auto-subtraction Operator	++ (Auto increment), -- (Auto increment)
Bitwise operators	(By bit or), & (by bit and ),~ (Bitwise inversion), ^ (bitwise XOR), <<< (left shift), >>( right shift)
Value assignment operator	=, + =,-=, * =,/=, % =, & =, ^ =, <=,> =
Space Application and release	New, delete, new [], delete []
Other operators	() (Function call),-> (member access), (comma), (subscript)

The following is a list of operators that cannot be overloaded:

.: Member access operator
. *,-> *: Member pointer access operator
: Domain operator
Sizeof: length Operator
? : Conditional Operators
#: Preprocessing symbol

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