What is Function Overloading in C++?
Two or more functions can have the same name but different parameters; such functions are called function overload in c++. The function overloading in the c++ feature is used to improve the readability of the code. It is used so that the programmer does not have to remember different function names. If a class has multiple functions with different parameters with the same name, they are said to be overloaded. If we need to perform a single operation with different numbers or types of arguments, we need to overload the function.
When I say parameter list, it means the data type and the order of the parameters. For example, the parameter list of a function myfunction(int a, double b) is (int, double), which is different from the parameter list of the function myfunction(double a, int b) parameter list(double, int). Function overloading is a compile-time polymorphism. As we already know what a parameter list is, let's see the rules of overload: we can have the following functions in the same scope.
som(int a, int b)som(int a, int b, int c)The easiest way to remember this rule is that the parameters must qualify one or more of the following conditions:
- They should have a different type
- They should have a different number
- They must have a different order of parameters.
Easy said,
Function overload in c++ can have the same name but different parameters
- What is function overloading in c++?
- Function overload in C++ Example
- Why is function overload used in c++?
- Function overload rules in C++
- What is the difference between function overload and override in C++?
- Causes of job overload
- Benefits of Function Overloading in C++
- Disadvantages of function overload in c++
- Difference Between Function Overload and Operator Overload
- Difference Between Job Overload and Job Domination
- Feature overload in C++ FAQ
- Conclusion
C++ has many features and one of its main features is feature overload. It is a code with more than one function with the same name and different kinds of argument lists. This argument list contains the data type of arguments and the order of the arguments.
Function overload in C++ example
Example 1:
#includemet namespace std; void SumNum(int A, int B);leegte SumNum(int A, int B, int C);leegte SumNum(int A, int B, int C, int D); int hoofd(){ SomNum(1,2); SomGetal(1,2,3); SomGetal(1,2,3,4); return 0;} void SumNum(int A, int B){ cout<< endl << "SUMNUM is : "<< A+B; } void SumNum(int A, int B, int C){ cout<< endl << "SUMNUM is : "<< A+B+C; } void SumNum(int A, int B, int C, int D){ cout<< endl << "SUMNUM is : "<< A+B+C+D; } Exit:SomNum is 3SumNum is 6SumNum is 10Example 2:
#includeusing namespace std;class Addition { public: int sum(int a,int b) { return a+b; } int som(int a,int b, int c) { return a+b+c; } };int main(void){ Toevoeging obj; cout< Exit:35191Why is function overload used in C++?
Function overload is similar to polymorphism that helps us to get different behavior, with the same name of the function. Function overloading in c++ is used for code reusability and to save memory.
Function overload rules in C++
Different parameters or three different conditions:
1. These functions have a different parameter type
as(int a, int b) as(double a, double b)2. These functions have a different number of parameters
som(int a, int b)som(int a, int b, int c)3. These functions have a different order of parameters
as(int a, double b) as(double a, int b)The above three cases are valid cases of overload. We can have any number of functions, but remember that the parameter list must be different. For example:
int mul(int, int)dubbel mul(int, int)Since the parameter list is the same, this is not allowed. Although their return types are different, it is not valid.
What is the difference between function overload and override in C++?
| Overload function | Overwrite function | |
| Definition | When two or more methods in a class have different parameters but have the same method name, it is called function overload. | One method is in the parent class and the other is in the child class when a function is overridden, but they have the same parameters and method name. |
| Feature signature | There must be a difference in the number or type of parameters. | The function signature must not change. |
| Behaviour | defines the behavior of different methods. | changes the way the procedure behaves. |
| Scope of the position | They belong to the same category. | They have a clear range. |
| Heritage | It can happen even without inheritance. | Only when one class inherits from another does it happen |
| Polymorphism | Compose time | Duration |
| Technology | code improvement method. | code replacement method. |
Function overload and ambiguity
The C++ programming language provides an overload function that allows an overload of two or more methods with the same name but different parameters to create compile-time polymorphism. Function and operator overload can be used to do this. While operator overload overloads operators to give user-defined data types some meaning, function overload overloads two or more functions with the same name but different parameters.
This feature allows the use of built-in operators on user-defined types. Operator overloading makes code easier to understand by redefining functionality to meet user needs. Both function overload and operator overload are discussed in detail in this article, as well as how they are applied in C++.
Using the Overloading idea, C++ makes it possible to create flexible and understandable code. It allows adding various functionalities to the existing code with a minimal number of changes, minimizing the need for duplicate code. In practice, C++ allows for two basic types of overload.
Function Overloading, a feature of C++, allows us to create functions with the same name but different data types or numbers of arguments supplied to them. This capability allows developers to define functions with the same name within the same scope. The named functions also share the same behavior, allowing for compile-time polymorphism. An advantage of function overload is that it makes the code more readable.
Using arguments can be used in any way to create function overload. The use of parameters can refer to a particular parameter type, a parameter count, or a parameter sequence. As a result, a function defined as calc(float x, int y) differs from calc(int x, float y), which has separate parameters with a different data type.
Types of function overload in c++
There are two types of function overload in c++-
- Compile time overload- When overloaded at compile time, functions are overloaded with different signatures. Signature of a function includes the return type, number of parameters, and types of parameters.
- Running time overload- Runtime overload overloads functions with a different number of parameters.
Causes of function overload in c++
- Type of conversion.
- Function with standard arguments.
- Function with a pass-by reference.
1. Type Conversion
Plan:
#includenamespace gebruiken std;void function(float);void function(int);void function(float x){std::cout << "Waarde van x is : " < Exit:
This example shows an error "call of overloaded 'function' is ambiguous". According to our prediction, function (3.4) will call the first function and function (34) will call the second function. But this is not what happens, because in C++ all floating point constants are not treated as float; instead they are treated as duplicates. If we replace the float variable with a double variable, the program will work properly. So we call it a type conversion error from float to double.
2. Function with standard arguments
Plan:
#includeusing namespace std;void function(int);void function(int,int); void function(int x){std::cout << "Waarde van x is : " < Exit:
The example above shows an error that says "calling overloaded 'fun(int)' is ambiguous", this is because function(int y, int z=12) can be called in two ways:
By calling the function with only one argument (and it will automatically take the value of z = 12)
By calling the function with only two arguments.
When you call the function function(12), we completely fill in the condition of both function(int) and function(int, int); therefore the compiler gets into an ambiguity which throws an error.
3. Function with a pass-by reference
Plan:
#includeuse namespace std;void function(int);void function(int &);void function(int a){std::cout << "Value of a is : " < Exit:
The above program shows an error message saying "call of overloaded 'fun(int&)' is ambiguous". As we see, the first function takes one integer argument and the second function takes a reference parameter as an argument. In this case, the compiler cannot understand which function the user needs, since there is no syntactic difference between fun(int) and fun(int &); therefore it shoots an ambiguity error.
Overload using different kinds of parameters
#includewith namespace std; void printValue(int A); void printValue(char A); void printValue(float A); int main(){ printValue(10); printValue('@' ); printvalue(3.14f ); return 0;} void printValue(int A){ cout<< endl << "Value of A : "<< A; } void printValue(char A){ cout<< endl << "Value of A : "<< A; } void printValue(float A){ cout<< endl << "Value of A : "<< A; } Output: Value of A: 10 Value of A: @Value of A: 3.14Function overloading can be implemented based on the many types of arguments passed to the function. Both non-member functions and member functions of a class can implement function overload.
Function overload by changing the number of arguments
Based on the amount of parameters entered into the function, we can implement function overload. Both non-member functions and member functions of a class can implement function overload.
#includemet namespace std; void SumNum(int A, int B);leegte SumNum(int A, int B, int C);leegte SumNum(int A, int B, int C, int D); int hoofd(){ SomNum(1,2); SomGetal(1,2,3); SomGetal(1,2,3,4); return 0;} void SumNum(int A, int B){ cout<< endl << "SUMNUM is : "<< A+B; } void SumNum(int A, int B, int C){ cout<< endl << "SUMNUM is : "<< A+B+C; } void SumNum(int A, int B, int C, int D){ cout<< endl << "SUMNUM is : "<< A+B+C+D; } Exit:SomNum is 3SumNum is 6SumNum is 10In this way of function overloading, we define two functions of the same type but with different number of parameters with the same names. For example, in the program below, we created two functions add() to return the sum of two and three integers.
// eerste functie definitionint add(int a, int b){cout << a+b;}// tweede overbelaste functie definitionint add(int a, int b, int c){cout << a+b+c;}Here the add() function is said to be overloaded because it has two definitions, one that can accept two arguments and another that can accept three arguments. Which add() function is called depends on the number of arguments.
int main() { add(10, 20); // add() with 2 parameters add(10, 20, 30); //sum() with 3 parameters}Program (By changing the number of arguments):
#includegebruik naamruimte std;int add(int a, int b){cout << a+b < Exit:60 90In the example above, we are overloading an add() function by changing the number of arguments. First, we define an add() function with the two parameters, and then we can overload it by defining another add() function, but this time with three parameters.
Function overload due to different types of arguments
In this method, we define two or more functions with the parameters of different data types, but with the same number of parameters with the same name. For example, in this program we have three add() functions; the first gets two integer arguments, the second gets two float arguments, and the third gets two double arguments.
Plan:
#includegebruik naamruimte std;int add(int x, int y) // eerste definitie{cout<< x+y << endl;return 0;}float add(float a, float b){cout << a+b << endl;return 0;}double add(double x, double y){cout << x+y << endl;return 0;}int main(){add(20, 40);add(23.45 f, 34,5f);optellen(40,24, 20,433);} Exit:6057.9560.673In the example above, we define an add() function three times. First by using integers as parameters, second by using float as parameters, and third by using double as parameter.
Therefore, we override the add() function twice.
Benefits of Function Overloading in C++
- The program is very simple and also easier to understand.
- It saves memory space, maintains consistency, makes clear interface for methods regardless of parameter type and program readability.
- Using the concept of function overload, we can develop more than one function with the same name, but the arguments passed must be of different types.
- Function overload makes the program run faster.
- Function overloading is used for code reusability and to save memory.
To clearly understand the overload of functions in C++, you need to be well versed in C++. If you want to improve your skills, you can use theIntroduction to C++ free courseat Great Learning Academy and learn the basic concepts and fundamentals of C++ to help you build expertise in the subject.
Disadvantages of function overload in c++
- Function declarations that differ by their return type cannot be overloaded with the function overload process.
- If a static member function is declared, the same parameters or same name types cannot be overloaded.
Difference Between Function Overload and Operator Overload
| Overload function | Operator overload |
| Function overload allows us to call it in multiple ways. | Operator overload allows operators to have their extended meaning beyond the predefined operational meaning. |
| You can overload the function with the same name but different parameters. | You can overload (define custom behavior) operators like '+', '-', '()', '[]'. |
| Feature overload means using a single name and giving it more functionality. | Operator overload means adding extra functionality for a particular operator. |
| When an operator is overloaded, the operator has different meanings, which depend on the type of operands. | When a function is overloaded, the same function name has different interpretations depending on the signature, the list of argument types in the function parameter list. |
To learn more about operator overload, visitOperatoroverbelasting in C++.
Difference Between Job Overload and Job Domination
| Overload function | Overwrite function | |
| Definition | In function overloading, two or more methods in one class have different parameters but the same method name. | When overriding functions, two methods have the same parameters and method name, but one method is in the parent class and the other is in the child class. |
| Feature Signature | The type of parameters or the number of parameters must be different. | Function signature must remain the same. |
| Behaviour | Defines multiple behaviors for a method. | Changes the behavior of the method. |
| Scope of the position | They fall in the same scope. | They have different scope. |
| Heritage | It can occur without inheritance. | It only occurs when a class is inherited from another class. |
| Polymorphism | Compose time | Duration |
| Technology | Code refinement technique | Code replacement technique |
| Number of classes | Only one class is required. | A minimum of two lessons are required. |
Feature overload in C++ FAQ
What is Function Overloading in C++?
Function overload refers to when two or more functions with the same name but different parameters exist.
Function overloading is one of the most crucial features of C++, among many other features. There are many functions with the same name in this code, each with a unique set of argument lists. The data type and the order of the arguments are also included in this argument list.
The overload feature of the C++ function is used to make the code more readable. It is used to avoid the programmer having to remember different function names. Overloaded functions are functions that belong to a class but have more than one instance with the same name but different parameters. The function should be overloaded if a single operation is to be performed with different numbers or types of parameters.
Function overload is called a function of polymorphism in OOP.
What is Declare Function Overload?
Similar to polymorphism, function overload allows us to obtain different behavior while preserving the name of the function. In C++, function overloading is used to reduce memory usage and increase code reuse.
What is C++ Runtime Polymorphism?
Late binding and dynamic polymorphism are other names for runtime polymorphism. The function call is resolved in runtime polymorphism at runtime. Unlike compile-time or static polymorphism, the compiler determines which function call to associate with the object after deriving it at runtime.
What is inheritance in C++?
By using inheritance, existing classes can be extended and reused without being modified, creating hierarchical links between the classes. A class can be embedded in an object through inheritance. Suppose you include a class A object of type x in the class specification of type B.
What are the benefits of job overload?
The fundamental advantage of function overload is that code is easier to read and reuse.
Function overloading is used to improve consistency, readability, and memory efficiency.
It speeds up the execution of the program.
In addition, maintenance of the code becomes easy.
Function overloading gives code flexibility.
The versatility of the function avoids the need for many function names to perform the same set of functions.
Conclusion
Function overloading in C++ can be used in several ways to improve code readability. While programming in C++ it helps save compile time and also saves memory space. You also learned how similar operations are performed using the concept of function overload.
You can improve your function overload in c++ drafts here:
Bron: GreatLearning-blog
Related
FAQs
What is function overloading in C++ explain with example? ›
The function overloading in the c++ feature is used to improve the readability of the code. It is used so that the programmer does not have to remember various function names. If any class has multiple functions with different parameters having the same name, they are said to be overloaded.
What is difference between overloading and overriding in C++? ›When two or more functions have the same name but their parameters are different, it is called function overloading. On the other hand, function overriding is one that provides a facility to redefine a function with a name and signature same as the inheriting class.
What are the ways to overload a function in C++? ›You overload a function name f by declaring more than one function with the name f in the same scope. The declarations of f must differ from each other by the types and/or the number of arguments in the argument list.
What are the different types of overloading in C++? ›There are mainly two types of overloading, i.e. function overloading and operator overloading.
What is overloading in C++ in simple words? ›The process of having two or more functions with the same name, but different parameters, is known as function overloading. The function is redefined by either using different types of arguments or a different number of arguments.
What is function overloading with real life example? ›In this example they (that family) hire some painter who knows only painting. If this family provides different types of statues to this painter then he has to do the work. In this way we can achieve overloading.
What is the difference between polymorphism and overriding? ›Polymorphism is a concept of object oriented programming that allows a field, in this case, an object, to be changed from one form to another. Poly = multiple, morph = change. Overriding a method, is essentially a dynamic binding of a method which allows a method to be changed during run-time.
Is overloading better than overriding? ›No. Method overloading is used to increase the readability of the program. Method overriding is used to provide the specific implementation of the method that is already provided by its super class.
What is the polymorphism in C++? ›Polymorphism means "many forms", and it occurs when we have many classes that are related to each other by inheritance. Like we specified in the previous chapter; Inheritance lets us inherit attributes and methods from another class. Polymorphism uses those methods to perform different tasks.
Which functions Cannot be overloaded in C++? ›Scope Resolution Operator (::) cannot be overloaded. Class member selector Operator (.) cannot be overloaded. Member pointer selector Operator (.*) cannot be overloaded. Object type Operator (typeid) cannot be overloaded.
How do you resolve an overloaded function? ›
- Gather all the functions in the current scope that have the same name as the function called.
- Exclude those that don't have the right number of parameters to match the arguments in the call. ...
- If no function matches, the compiler reports an error.
The two member access operators, operator->() and operator->*() can be overloaded. The most common use of overloading these operators is with defining expression template classes, which is not a common programming technique.
What is the other name for function overloading? ›In Java, function overloading is also known as compile-time polymorphism and static polymorphism. Function overloading should not be confused with forms of polymorphism where the choice is made at runtime, e.g. through virtual functions, instead of statically.
What are the advantages of function overloading? ›Advantages of function Overloading in C++
Function overloading speeds up the execution of the program. Function overloading is used for code reusability and also to save memory. It helps application to load the class method based on the type of parameter. Code maintenance is easy.
Polymorphism in C++ allows us to reuse code by creating one function that's usable for multiple uses. We can also make operators polymorphic and use them to add not only numbers but also combine strings. This saves time and allows for a more streamlined program.
What is the conclusion of function overloading in C++? ›In Conclusion, function overloading feature in C++ can be used in multiple ways to increase code readability. It helps in saving memory space as well as compilation time while programming with the C++ language.
What is the difference between constructor and destructor in C++? ›A constructor allows an object to initialize some of its value before it is used. A destructor allows an object to execute some code at the time of its destruction.
What is function overloading syntax? ›Syntax. As explained from the definition of Function Overloading in C++, to overload two or more functions, they must have the same function name and different parameters that are either a different number of parameters or different data types of parameters or both.
What is example of overloading? ›It can be understood in simple terms with a simple example. A class addition has two methods named add(), one method has parameters int a and int b, while the other has three integer parameters, i.e., int a, int b, and int c. Therefore, the add() method is said to be overloaded.
What are the three types of polymorphism? ›Polymorphism means "many forms" and is the opposite of uniform. In Object-Oriented programming languages there are three types of polymorphism: subtype polymorphism, parametric polymorphism, and ad-hoc polymorphism.
What are the two main types of polymorphism? ›
There are two types of polymorphism which are the compile-time polymorphism (overload) and run-time polymorphism (overriding).
What is the difference between polymorphism and inheritance? ›The most basic difference between inheritance and polymorphism is that "inheritance" is a concept of objectoriented programming that allows creating a new class with the help of the features of an existing class, whereas the concept "polymorphism" represents multiple forms of a single function.
Can you override a constructor? ›Constructor looks like method but it is not. It does not have a return type and its name is same as the class name. But, a constructor cannot be overridden.
Can final method be overloaded? ›yes overloading final method is possible in java.As final methods are restricted not to override the methods. while overloading argument list must be different type of the overloading method.
Can static methods be overloaded? ›Notes. The static method is resolved at compile time cannot be overridden by a subclass. An instance method is resolved at runtime can be overridden. A static method can be overloaded.
What is a real life example of polymorphism? ›Even animals are great real life example of polymorphism, if we ask different animals to speak, they respond in their own way. Like if we ask Dog to speak it will bark, similarly, cow will moo, cat will meow. So the same action of speaking is performed in different ways by different animals exhibiting polymorphism.
What is encapsulation in C++ with example? ›In general, encapsulation is a process of wrapping similar code in one place. In C++, we can bundle data members and functions that operate together inside a single class. For example, class Rectangle { public: int length; int breadth; int getArea() { return length * breadth; } };
Can a free function be overloaded? ›You can overload both member functions and free functions. The following table shows which parts of a function declaration C++ uses to differentiate between groups of functions with the same name in the same scope.
Can we overload all operators in C++? ›You can redefine or overload the function of most built-in operators in C++. These operators can be overloaded globally or on a class-by-class basis. Overloaded operators are implemented as functions and can be member functions or global functions. An overloaded operator is called an operator function.
Can virtual function be overloaded in C++? ›It is not possible for these functions to get overloaded.
What is ambiguity in function overloading? ›
In C++, Ambiguity in Function Overloading is a situation that occurs when the compiler is unable to choose one function from all the overloaded functions for execution. This occurs mostly while passing floating-point numbers as variables to an overloaded function.
Why function overloading is a bad idea? ›In general, overloading adds complexity to the language; it tends to interact with all sorts of other features, making those features harder to learn, harder to use, and harder to implement.
What are the 2 ways to overload a function? ›Overloading Methods
Method overloading can be achieved by the following: By changing the number of parameters in a method. By changing the order of parameters in a method. By using different data types for parameters.
When we have multiple functions with the same name but different parameters, then they are said to be overloaded. This technique is used to enhance the readability of the program. Function overloading is normally done when we have to perform one single operation with different number or types of arguments.
Which type of function Cannot be overloaded? ›If two functions are exactly same but differed only in default arguments i.e. one of the functions contains default arguments, then they are considered as same which means they can't be overloaded and therefore compiler will throw an error of redeclaration of the same function.
What is the most popular form of operator overloading? ›The most frequent instance is the adding up operator '+', where it can be used for the usual addition and also for combining two different strings. As mentioned on top, the plus symbol's practice in dissimilar forms is the largest classic example of the operator level overloading process.
What is the difference between operator overloading and operator overriding? ›When the method signature (name and parameters) are the same in the superclass and the child class, it's called overriding. When two or more methods in the same class have the same name but different parameters, it's called overloading.
What is the difference between unary and binary operator overloading in C++? ›In summary, the main difference between unary and binary operators is the number of operands they take - unary operators take one operand, while binary operators take two operands.
Is function overloading a polymorphism? ›Method/function overloading is an implementation of compile-time polymorphism where the same name can be assigned to more than one method or function, having different arguments or signatures and different return types.
Is function overloading called polymorphism? ›Polymorphism in Function Overloading
In computing, polymorphism is a property of object oriented programming in which a function can take different forms based on the number of arguments and their data types. All the functions will have the same name, but they will differ in their arguments.
What is function overloading and overriding explain with an example? ›
Function overloading is used when we want multiple functions providing a similar implementation. However, function overriding is used when we want to add some additional functionality on top of base class implementation.
What is function in C++ with example? ›A function definition provides the actual body of the function. The C++ standard library provides numerous built-in functions that your program can call. For example, function strcat() to concatenate two strings, function memcpy() to copy one memory location to another location and many more functions.
Is function overloading in C++ example of polymorphism? ›Function overloading means one function can perform many tasks. In C++, a single function is used to perform many tasks with the same name and different types of arguments. In the function overloading function will call at the time of program compilation. It is an example of compile-time polymorphism.
What do you mean by overloading? ›The current in a circuit depends on the rating of the appliances connected to it. If the total current drawn through a wire by the appliances connected to it exceeds the safety limit for that wire, it gets overheated. This is known as overloading.
What is the difference between function overloading and polymorphism? ›Polymorphism is the process to define more than one body for functions/methods with same name. Overloading IS a type of polymorphism, where the signature part must be different. Overriding is another, that is used in case of inheritance where signature part is also same.
What is difference between overloading and overriding? ›When two or more methods in the same class have the same method name but different parameters, this is called overloading. In contrast, overriding occurs when two methods have the same name and parameters.
What are the 4 types of functions? ›Constant Function: The polynomial function of degree zero. Linear Function: The polynomial function of degree one. Quadratic Function: The polynomial function of degree two. Cubic Function: The polynomial function of degree three.
What is function in C++ in simple words? ›A function is a block of code that performs some operation. A function can optionally define input parameters that enable callers to pass arguments into the function. A function can optionally return a value as output.
What is array in C++ with example? ›In C++, an array is a variable that can store multiple values of the same type. For example, Suppose a class has 27 students, and we need to store the grades of all of them.
What is the real life example of function overriding in C++? ›Example 1: C++ Function Overriding
So, when we call print() from the Derived object derived1 , the print() from Derived is executed by overriding the function in Base . As we can see, the function was overridden because we called the function from an object of the Derived class.
Which polymorphism can be used instead of overloading? ›
Ad hoc polymorphism is what you described in your Overloading section and is a case of polymorphism.
What are the two types of polymorphism in C++? ›It is of two types: Compile-time Polymorphism and Runtime Polymorphism.
What are the three types of overloading? ›1) When an Object has Same Name. 2) Difference is Return type. 3) Difference in Function, with Multiple Arguments.
What are the 3 causes of overloading? ›There factors which can cause overloading are : (1) Direct contact of the live wire and neutral wire . (2) Accidental high rise in the supply voltage . (3) Connecting too may appliances to a single socket and using them simultaneously.