C++ Programming Code Examples
C++ > Beginners Lab Assignments Code Examples
Inheritance allows the child class to acquire the properties
/* Inheritance allows the child class to acquire the properties
Inheritance is one of the feature of Object Oriented Programming System(OOPs), it allows the child class to acquire the properties (the data members) and functionality (the member functions) of parent class.
What is child class?
A class that inherits another class is known as child class, it is also known as derived class or subclass.
What is parent class?
The class that is being inherited by other class is known as parent class, super class or base class. */
#include <iostream>
using namespace std;
class Teacher {
public:
Teacher(){
cout<<"Hey Guys, I am a teacher"<<endl;
}
string collegeName = "Happy College :)";
};
//This class inherits Teacher class
class MathTeacher: public Teacher {
public:
MathTeacher(){
cout<<"I am a Math Teacher"<<endl;
}
string mainSub = "Math";
string name = "Jack";
};
int main() {
MathTeacher obj;
cout<<"Name: "<<obj.name<<endl;
cout<<"College Name: "<<obj.collegeName<<endl;
cout<<"Main Subject: "<<obj.mainSub<<endl;
return 0;
}
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.
The cout is a predefined object of ostream class. It is connected with the standard output device, which is usually a display screen. The cout is used in conjunction with stream insertion operator (<<) to display the output on a console. On most program environments, the standard output by default is the screen, and the C++ stream object defined to access it is cout. The "c" in cout refers to "character" and "out" means "output". Hence cout means "character output". The cout object is used along with the insertion operator << in order to display a stream of characters.
In C++, constructor is a special method which is invoked automatically at the time of object creation. It is used to initialize the data members of new object generally. The constructor in C++ has the same name as class or structure. Constructors are special class functions which performs initialization of every object. The Compiler calls the Constructor whenever an object is created. Constructors initialize values to object members after storage is allocated to the object. Whereas, Destructor on the other hand is used to destroy the class object. • Default Constructor: A constructor which has no argument is known as default constructor. It is invoked at the time of creating object.
The main purpose of C++ programming is to add object orientation to the C programming language and classes are the central feature of C++ that supports object-oriented programming and are often called user-defined types. A class is used to specify the form of an object and it combines data representation and methods for manipulating that data into one neat package. The data and functions within a class are called members of the class.
In C++, inheritance is a process in which one object acquires all the properties and behaviors of its parent object automatically. In such way, you can reuse, extend or modify the attributes and behaviors which are defined in other class. In C++, the class which inherits the members of another class is called derived class and the class whose members are inherited is called base class. The derived class is the specialized class for the base class. You can reuse the members of your parent class. So, there is no need to define the member again. So less code is required in the class.
Execute system command. Invokes the command processor to execute a command. If command is a null pointer, the function only checks whether a command processor is available through this function, without invoking any command. The effects of invoking a command depend on the system and library implementation, and may cause a program to behave in a non-standard manner or to terminate.
Consider a situation, when we have two persons with the same name, jhon, in the same class. Whenever we need to differentiate them definitely we would have to use some additional information along with their name, like either the area, if they live in different area or their mother's or father's name, etc. Same situation can arise in your C++ applications. For example, you might be writing some code that has a function called xyz() and there is another library available which is also having same function xyz(). Now the compiler has no way of knowing which version of xyz() function you are referring to within your code.
A predefined object of the class called iostream class is used to insert the new line characters while flushing the stream is called endl in C++. This endl is similar to \n which performs the functionality of inserting new line characters but it does not flush the stream whereas endl does the job of inserting the new line characters while flushing the stream. Hence the statement cout<<endl; will be equal to the statement cout<< '\n' << flush; meaning the new line character used along with flush explicitly becomes equivalent to the endl statement in C++.
Program, using recursion, evaluates a Prefix Expression in an "Expression Tree". A binary expression tree is a specific application of a 'binary tree' to evaluate certain expressions.
