Programming Concepts

• 1. How to solve Programming problem
• 2.How a computer executes a program
• 3. What is a "data type" and its fundamental role in writing a program
• 4. The role of characters---the basic building blocks of all programs
• 5. The concepts of constants and variables

 How to computer solve problem

Solving a problem on a computer involves the following activities:

•    1. Define the problem
•    2. Analyze the problem
•    3. Devlop an algorithm(a method) for solving the problem
•   4. Data and Variables

Introduction  of  C++

Structure of C++ Program :

 A C++ Program has four subparts as shown in block diagram . These subparts can be kept in different- different source files and after it can be compile separately or together.

Include file

Declaration of class

Defebition of member function

main() function

           Structure of C++ program

A simple program of C++

Program to print "Good morning" on output screen-

Program - A simple program of C++

#include<iostream>.h                             // include header file

using namespace std;                          //but you can replace #include<stdio>.h

int main()

{

            cout <<"Good morning ";            //print "Good morning"

            return0;

}

Output of above program will be-

Good Morning

 Features of C++ program

• Just like C,C++ program is also collection of functions.
• It is compulsory to write main() function in C++ programs.
• In C++ program statements ends with semicolon (;) like C program.​

Comments- 

1. (Double slash ) is used to write comments of a single line.        ​
2. /*.....*/ is used to write comments of more than one line.​​

io stream file-

1. The statements which has # sign are know as pre-processor directives.
2. These are written at the starting of C++ program.
3. Preprocessor procrss these statements before compilation of program.
4. #include<iostream> - This statement add contents of iostream file to the content of program.
5. In it cout identifier and insertion oprators are declared.

Namespace-

1. It defines the scope of identifier used in a program.
2. To use Namespace scope 'using namespace std' is written.
3. 'std' is a namespace which is defined in standard class library of C++.

Compile and linking-

             Compiling and linking process depends upon operating system.

    Linux OS

• ​      g++ command is used for compiling and linking of C++ program.
•       Example- g++ abc.cpp.

This command compiles the program written in abc.cpp file. Compiler creates a object file abc.0 and which creates and executable file linking with library functions. Default executable file name is a.out.