C++ Tutorial Index

C++ Tutorial C++ History C++ Installation C++ First Program C++ cin and cout C++ Data type C++ Variable C++ operator C++ Keywords

C++ Control Statements

C++ If C++ Nested if C++ If-else C++ If-else-if C++ Switch C++ Break C++ Continue C++ Goto C++ For loop C++ While loop C++ Do while loop

C++ Functions

C++ Call by Value C++ Call by Reference C++ Recursion Function C++ Inline function C++ Friend function

C++ Arrays

Single dimension array Two dimension array

C++ Strings

C++ Strings

C++ Inheritance

C++ Inheritance Single level Inheritance Multilevel Inheritance Multiple Inheritance Hierarchical Inheritance Hybrid Inheritance

C++ Polymorphism

C++ Polymorphism C++ Overloading C++ Overriding C++ Virtual Function

C++ Pointers

C++ Pointers C++ this pointer

C++ Exception Handling

C++ Exception Handling

C++ Constructors

C++ Constructors Default Constructor Parameterize Constructor Copy constructor Constructor Overloading Destructor

C++ File Handling

C++ File Handling C++ Writing to file C++ Reading file C++ Close file

Miscellaneous

C Vs C++ C++ Comments C++ Data Abstraction C++ Identifier C++ Memory Management C++ Storage Classes C++ Void Pointer C++ Array To Function C++ Expressions C++ Features C++ Interfaces C++ Encapsulation std::min in C++ External merge sort in C++ Remove duplicates from sorted array in C++ Precision of floating point numbers Using these functions floor(), ceil(), trunc(), round() and setprecision() in C++ C++ References C++ Friend Functions C++ Mutable keyword Unary Operators in C++ Initialize Array of objects with parameterized constructors in C++ Differences between #define & const in C/C++ C++ Program to Implement Shell Sort C++ Program to Implement Merge Sort Storage Classes in C Vector resize() in C++ Passing by Reference Vs. Passing by the pointer in C++ Free vs delete() in C++ goto statement in C and C++ C++ program to read string using cin.getline() C++ String Concatenation Heap Sort in C++ Swap numbers in C++ Input Iterators in C++ Fibonacci Series in C++ C ++ Program: Alphabet Triangle and Number Triangle C++ Program: Matrix Multiplication C++ Program to Print Fibonacci Triangle Stack in C++ Maps in C++ Queue in C++ C++ Bitset C++ Algorithms Priority Queue in C++ C++ Multimap C++ Deque Function Pointer in C++ Sizeof() Operators in C++ C++ array of Pointers free() Vs delete in C Timsort Implementation Using C++ CPP Templates C++ Aggregation C++ Enumeration C++ Math Functions C++ Object Class C++ Queue Initialize Vector in C++ Vector in C++ C++ STL Components Function overloading in C++ C++ Maximum Index Problem C++ find missing in the second array C++ Program to find the product array puzzle C++ Program To Find Largest Subarray With 0 Sum C++ Program To Move All Zeros To The End Of The Array C++ Program to find the element that occurs once C++ Program to find the largest number formed from an array Constructor Vs Destructor C++ Namespaces C++ OOPs Concept C++ Static C++ Structs C++ Try-Catch C++ User Defined Exceptions C++ Virtual Destructor C++ vs C# Malloc() and new in C++ Palindrome Number Program in C++ Snake Code in C++ Splitting a string in C++ Structure Vs Class in C++ Virtual Function Vs Pure Virtual Function C++ Bidirectional Iterators C++ Forward Iterators C++ Iterators C++ Output Iterators C++ Range-based For Loop Converting string into integer in C++ LCM Program in C++ Type conversion in C++ Add two numbers using the function in C++ Advantage and disadvantage friend function C++ Armstrong Number Program in C++ ATM machine program in C++ using functions Binary to Decimal in C++ Bit Manipulation in C++ C++ Constructor C++ Dijkstra Algorithm Using the Priority Queue C++ int into String C++ Signal Handling Decimal to Binary in C++ Decimal to Hexadecimal in C++ Decimal to Octal in C++ Factorial Program in C++ Function in C++ Hexadecimal to Decimal in C++ Octal to Decimal in C++ Reverse a Number in C++ Structure Vs Class in C++ C++ Forward Iterators C++ Output Iterators C++ Prime number program Char Array to String in C++ Constructor Overloading in C++ Default arguments in C++ Different Ways to Compare Strings in C++ Dynamic Binding in C++ Program to convert infix to postfix expression in C++ SET Data Structure in C++ Upcasting and Downcasting in C++ Reverse an Array in C++ Fast Input and Output in C++ Delete Operator in C++ Copy elision in C++ C++ Date and Time C++ Bitwise XOR Operator Array of sets in C++ Binary Operator Overloading in C++ Binary Search in C++ Implementing the sets without C++ STL containers Scope Resolution Operator in C++ Smart pointers in C++ Types of polymorphism in C++ Exception Handling in C++ vs Java Const Keyword in C++ Type Casting in C++ Static keyword in C++ vs Java Inheritance in C++ vs Java How to concatenate two strings in C++ Programs to Print Pyramid Patterns in C++ swap() function in C++ Structure of C++ Program Stringstream in C++ and its applications rand() and srand() in C / C++ C++ Ternary Operator C++ Scope of Variables While Loop Examples in C++ Star pattern in C++ using For Loops For Loop Examples in C++ Do-While Loop Examples in C++ Top 5 IDEs for C++ That You Should Try Once Assertions in C/C++ C++ Convert Int to String Continue in C++ While loop Diamond Pattern in C++ using For Loop How to Reverse a String in C++ using Do-While Loop How to Reverse a String in C++ using For Loop How to Reverse a String in C++ using While Loop Infinite loop in C++ Loops in C++ Returning Multiple Values from a Function using Tuple and Pair in C++ wcscpy(), wcslen(), wcscmp() Functions in C++ Auto keyword in C++ C++ 11 vs C++ 14 vs C++ 17 C++ STL (Standard Template Library) Differences Between C Structures and C++ Structures Divide by Zero Exception in C++ Dynamic Constructor in C++ Dynamic Memory Allocation in C++ Find the Size of Array in C/C++ without using sizeof() function Floating Point Operations and Associativity in C, C++ and Java Hello World Program in C++ How to create a table in C++ How to Setup Environment for C++ Programming on Mac Implementation of a Falling Matrix in C++ Message Passing in C++ Pointer to Object in C++ Templates in C++ vs Generics in Java Ways to Copy a Vector in C++ What does Buffer Flush mean in C++ sort() function in C++ Structure Sorting (By Multiple Rules) in C++ Similarities between C++ and Java std::distance in C++ Array program in C++ C++ Tricks for Competitive Programming Desired Capabilities in Selenium Web Driver in C++ Socket Programming in C++ Template Specialization in C++ Classes and Objects in C++ Convex hull Algorithm in C++ DES in C++ C++ vardiac() function Difference between Two Sets in C++ Difference between Exit and Return Structured Binding in C++ Differences between Local and Global Variable Bitwise Operator vs Logical Operator Difference between OOP and POP in C++ Fork in C++ Functors in C++ How to call a void function in C++ How to create a directory or folder in C/C++ How to create a library in C++ How to create a stack in C++ How to create the Processes with Fork in C++ How to Handle Divide by Zero Exception in C++ Lambda Expression in C++ Pattern programs in C++ Roadmap to C++ Programming Substring in C++ Virtual base class in C++

Constructor Overloading in C++

A Constructor is a class member function that is used to initialize the class's objects. Constructors have no return type and are called automatically when an object is formed.

Constructor Characteristics

  • Constructors don't have a return type.
  • When the object is created, it is immediately called. It is always placed in the class's public scope.
  • If no constructor is specified, the default constructor is used, which sets the value of the data member to zero.
  • The name of the function Object ( ) { [native code] } is case-sensitive.
  • A function Object ( ) { [native code] } is not inherited by default.

Types of Constructor

Default Constructor: It's used to assign a value to data members. When an object is created, the default function Object () { [native code] } is invoked.

Example:

#include < iostream >  
#include < bits/tsdc++.h >
#include < stdlib >
using namespace std ;  
class construct  // create a class construct  
{  
public:  
    int x , y ; // initialise two data members   
    construct ( ) // this is how default constructor is created   
    {  
        // We can also assign both values to zero   
        x = 10 ; // intialise x with some value   
        y = 20 ; // initialise y with some value  
    }  
} ;  
int main ( )  
{     
    construct z ; // creating an object of construct calls defualt constructor  
    cout << "x:" << z.x << endl ;
        << "y:" << z.y ; // print x and y
    return 1 ;  
}  

OUTPUT:

X: 10
Y:20
……..
Process executed in 0.11 seconds
Press any key to continue.

Explanation:

In the program above in C ++, we created a builder class and announced the default builder. In the main work we started the builder thing by z.

Parameterized Constructor is non-parameterized function Object() { [native code] } has function Object() { [native code] } arguments, and the value supplied in the argument is initialised to its data members. Parameterized constructors are utilised in function Object() { [native code] } overloading.

Example:

#include < iostream >  
#include < bits/stdc++.h >
#include < stdlib >
using namespace std ;  
class Point // create point class  
    {  
private :  
int a , b ; // the two data members of class Point  
public :  
Point ( int a1 , int b1 ) // create paramterised Constructor and initialise data member  
    {  
        a = a1 ; // a1 is now intialised to a  
        b = b1 ; // a1 is now intialised to b  
    }  
intgetA ( )  
    {  
return a ; // to get the value of a  
    }  
intgetB ( )  
    {  
return b ; // to get the value of b  
    }  
} ;  
int main ( )  
{  
Point pt1 ( 10 , 15 ) ; // created object for paramterised constructor  
cout << "pt1.a = " << pt1.getA ( ) << " , pt1.b = " << pt1.getB ( ) ; // print a and b 
return 0 ;  
}

OUTPUT:

Pt1.a = 10 ,pt1.b = 15
……………………………..
Process executed in 0.11 seconds
Press any key to continue.

Explanation:

Make a class point out of the two data elements a and b. A parameterized constructor is formed using the parameters a1 and b1, and the values of a and b are assigned using a1 and b1. We build a parameterized constructor using the values in the main function (10, 15). The values of the data members are obtained using the getter functions.

Constructor Overloading

Similarly to the idea of function overloading, constructor overloading is used. Constructor overloading occurs when we overload a function Object with more than one purpose. The conditions for overloading a function Object are to change the number or type of parameters.

Example:

// C++ program to demonstrate constructor overloading  
#include <iostream>  
using namespace std;  
class People { // create people class  
private:  
int Age; // data member  
public:  
    // 1. Constructor with no arguments  
People ()  
    {  
Age = 10; // when object is created the age will be 20  
    }  
    // 2. Constructor with an argument  
People (int a)  
{ // when parameterised Constructor is called with a value the  
        // age passed will be initialised  
Age = a;  
    }  
intgetage()  
{ // getter to return the age  
return Age;  
    }  
};  
int main()  
{  
People person1 , person2 ( 20 ) ; // called the object of people class in differnt way  
cout<< "Person1 Age = " << person1.getage() <<endl;  
cout<< "Person2 Age = " << person2.getage() <<endl;  
return 0;  
}  

OUTPUT:

Person1 Age = 10
Person2 Age = 20
………………………..
Process executed in 0.11 seconds
Press any key to continue.

Explanation:

In the preceding program, we established a People class with one data member (Age). We've overloaded the second by passing it one argument and parameterzing it. As a result, when the object person1 age is printed, it returns the default value of 20, however person2 age returns 45 since it was supplied by the object to the parameterized constructor.



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