Introduction to C++ Programming Language

As a beginner, choosing the right programming language is a tough task in order to start developing your coding skills. Well, C++ is a programming language that you can choose as a beginner. C++ has become a widely used language that is applicable in system software, game development, embedded systems, financial software, and high-performance computing. In this article, we will discuss the introduction to C++, the evolution and history of C++, its features, syntax and structure, fundamental concepts, uses, and comparison with other programming languages.

Table of Contents:

• What is C++?
• History and Evolution of C++
• Why You Should Learn C++?
• How to Use C++?
• Features of C++
• Syntax and Structure of C++
• Core Concepts in C++
• Applications of C++
• Best Practices for C++ Programming
• C++ vs Other Programming Languages
• Conclusion

What is C++?

C++ is a high-level programming language designed for flexible, scalable, and efficient programming, as it supports both procedural and object-oriented programming. It can be used in system programming, game development, embedded systems, and application development with high performance. It provides you with features such as classes, inheritance, polymorphism, templates, and the Standard Template Library (STL). Also, it supports manual memory management, multi-threading, and low-level system access, which makes it ideal for resource allocation.

History and Evolution of C++

Bjarne Stroustrup at Bell Labs developed C++ as an extension to C programming language in the early 1980s. He merged the low-level features of C with modern programming features such as object-oriented programming (OOP) which led to the development of “C with Classes”, which was later known as C++ programming language.

Versions of C++ Programming Language

Now, let’s discuss different versions of C++ that have evolved over the period of time from its initial phase:

Phase 1: C++98 (1998) – First Standardized Version

C++ was standardized by the International Organization for Standardization (ISO) in 1998. In this version, the Standard Template Library (STL) was released which has containers, algorithms, and iterators, which helped to improve the code reusability and efficiency.

Phase 2: C++11 (2011) – Modern C++ Begins

The C++11 version played an important role in the evolution of basic C++, as it introduced smart pointers for better memory management, lambda expressions for functional programming, and move semantics for performance efficiency. 

Phase 3: C++17 (2017) – Performance and Convenience

The C++17 version simplified the code and enhanced performance with features such as structured bindings and file handling, which made it easier to work with tuples, pairs, and files.

Phase 4: C++20 (2020) – Major Modernization

C++ 20 released concepts that provide better compile-time validation and coroutines that simplify asynchronous programming. Also, it provided modules and ranges which helped to improve the compilation speed and efficiency.

Phase 5: C++23 and Later

The C++23 version continued the modernization of C++ with better constexpr features, range algorithms, and networking support, and the coming versions will make the C++ programming language even easier while maintaining its high performance.

For more information about all the C++ versions, check this table:

Syntax and Structure of C++

C++ has a well-defined case-sensitive syntax and structure. Below is a brief description of the basic syntax and structure of a C++ program, which will help you learn coding in C++ as a beginner.

1. Structure of a C++ Program

The structure is referred to as the organization of a C++ program with its components, which defines how every part of the program is arranged to make it readable and easily executable.

A simple C++ program has:

1. Preprocessor Directives: #include is a preprocessor directive used in C++ for importing libraries.

#include <iostream>  //1. Preprocessor directive

2. Namespace: The std namespace is used in C++ which defines the scope.

using namespace std;  //2. Namespace declaration

3. Main Function: The main() function works as the entry point of the program.

int main() {  // 3. Main function (entry point)

4. Statements: C++ programs have code logic, which is enclosed in { }.

cout << "Hello, World!" << endl;  // 4. Statements

5. Return Statement: It returns the value and ends the main function with the exit code.

return 0;  // 5. The return statement which returns the value

2. Syntax of a C++ Program 

Syntax is a set of rules that defines how a C++ program should be written so that it is easily and correctly understood by the compiler. It is important in the program to follow the correct grammar, punctuation, and order of commands.

C++ Syntax Rules:

• Every statement must end with a semicolon (;).
• Code blocks in C++ must be enclosed within curly braces { }.
• As C++ is case-sensitive, Main and main would be treated differently.
• Data types must be declared properly for efficient memory management and correct computations.

Example:

int x = 10; // Correct syntax
int x 10;   // Incorrect syntax as the '=' operator is missing

Explanation: The code shows you how to initialize the variable x with value 10 in the correct manner in the first line, and the second line shows that due to the missing ‘=’ operator x is not initialized correctly and it will give an error in the program.

Write Your First C++ Program

Now, as we have discussed the structure and syntax of C++, let’s start writing your first classic C++ “Hello, World!” program. Open your compiler and type the following:

Output:

You can also try running this code here and experimenting with different outputs.

Code Explanation: The code shows that the C++ program starts with a preprocessor directive which includes the iostream library for the input and output operations and also uses the std namespace. The main function works as the entry point in the program where cout prints the given message to the console with the return 0 statement which shows the successful execution of the program.

How to Use C++?

Below are a few steps are given which you must follow to use C++ on your personal computer:

1. Install a C++ Compiler – To run C++ programs at first you should install a compiler like GCC (MinGW for Windows), Clang, or MSVC or IDEs such as Code::Blocks, Dev-C++, or Visual Studio come with built-in compilers.
2. Write Code in a Text Editor or IDE – Use an IDE (Integrated Development Environment) like Code::Blocks, Visual Studio, or JetBrains CLion, or a text editor like VS Code or Notepad++ to write your C++ code.
3. Compile the Code – Now, save the file with a .cpp extension and compile it using a command like:

g++ program.cpp -o program

4. Run the Executable Code – Execute the compiled program:

./program  # On Linux/Mac

program.exe  # On Windows

5. Debug and Improve – At last use the debugging tools in IDEs or command-line debuggers such as gdb to fix errors and optimize your C++ program.

Features of C++ 

Below we have discussed the main features of C++ that help you to understand this programming language in more detail and develop your coding skills.

1. Object-Oriented Programming: C++ has OOP features which is why it supports encapsulation, inheritance, polymorphism, and abstraction and makes the code more reusable and modular.
2. Multi-Paradigm Support: It supports procedural, object-oriented, generic programming in a single language.
3. Low-Level Memory Manipulation and High Performance: C++ provides low-level memory manipulation yet runs faster than many other high-level languages.
4. Manual Memory Management: It supports manual memory management with the help of pointers, new or delete operators, and smart pointers.
5. Standard Template Library: The Standard Template Library (STL) in C++ provides predefined classes and functions.
6. Cross-Platform Compatibility: Also, C++ can easily run on multiple operating systems with only minimal changes.
7. Language Integration: It can easily integrate with other programming languages such as C, Python, and Assembly.
8. Multi-Threading Support: C++ also supports multi-threading for parallel programming and performance optimization.
9. Type Safety: It makes sure that code can be executed with the correct type.
10. Versatility in Application Development: C++ is suitable for small applications, enterprise applications, and high-performance computing.

Core Concepts in C++

C++ is a powerful and versatile programming language that supports procedural, object-oriented, and generic programming concepts, thus, it has some fundamental concepts that make the foundation of C++ programming.

1. Variables and Data Types

Variables are used to store the values in the memory and the data types are used to define the type of data that the variables had stored in C++.

Example:

Output:

Explanation: The code shows how the four variables, an integer(age), a floating point number(pi), a character(grade), and a boolean(isPass) of different data types are declared and initialized with different values, and their values are printed using the std::cout.

2. Operators 

The C++ programming language provides various types of operators to perform mathematical, logical, and bitwise operations.

Example:

Output:

Explanation: The code shows how the operations are done using the operators in C++, the first cout statement in the above code will print 15 by adding a and b, and the second cout statement will print 1 as the expression (a>b) evaluates to true.

3. Control Structures

The control structure in C++ determines the flow of code execution.

a) Conditional Statements 

The conditional statements in C++ allow the program to make decisions based on particular conditions. The main types of conditional statements are if, if-else, nested if-else, and switch.

Now let’s understand these conditional statements with the help of a few examples

If-else Example:

Output:

Explanation: The code shows how the if-else is used in the C++ program, as it checks if the number is greater than 0, and if it is so, then it will print “A positive number” or else it will print “A negative number”, and here number 10 is greater than 0, thus, the output is “A positive number”.

Switch Example:

Output:

Explanation: The code shows how the switch case is used in the C++ program since the code checks the value of the grade using the switch, and if the grade is A then it will match case ‘A’ and will print “Excellent”, and if the grade is B then it will print “Good”, and for some other value it will print “Try again”, and here the grade is A, thus, the output is Excellent.

b) Loops 

In C++, loops help a block of code to get executed a number of times until a particular condition is met. There are three main types of loops in C++ such as for loop, while loop, and do-while loop.

For Loop Example:

Output:

Explanation: The code shows how the for loop is used in the C++ program, as in this code, the for loop initializes i to 0, increments i by 1 on every iteration, and runs till i is less than 5, and then the numbers from 0 to 4 are printed.

While Loop Example:

Output:

Explanation: The code shows how the while loop is used in the C++ program as it initializes x to 0 and increments x by 1 in every iteration until less than 5, and then, the std::cout prints the numbers from 0 to 4 to the console.

Example for Do-While Loop (executes at least once):

Output:Output:

Explanation: The code shows how the do-while loop is used in the C++ program as it executes the code block at least once, prints y, and increments y until it reaches 6, and then prints the numbers from 0 to 5 to the console.

4. Functions 

Functions in C++ are used to modularize codes by dividing them into smaller and reusable blocks.

Syntax:

returnType functionName(parameters) {
    // Function body
}

Example:

Output:

Explanation: The code shows how a function add(int a, int b) is defined in a C++ program that returns the sum 15 of a and b, and in the main() function this function is called with the values 5 and 10.

5. Object-Oriented Programming (OOP) Concepts

C++ is basically an object-oriented programming language, thus, it supports the below-given features:

a) Classes and Objects

Classes in C++ are the blueprints that create objects, and the objects are instances of the classes.

Example:

Output:Output:

Explanation: The code shows how the concept of classes and objects works in the C++ program, in this code a Car class is defined with two attributes brand and speed, and in the main() function an object myCar is created with the values assigned attributes which will print the output using display() method.

b) Encapsulation

Encapsulation is a feature in C++ that bundles data and methods together without giving direct access to them.

Now let’s understand the encapsulation with the help of an example in C++

Example:

Output:

Explanation: The code shows the encapsulation concept works in a C++ program since a Student class is defined with a private attribute age which can be accessed through the public setter (setAge) and getter (getAge) methods, and in the main() function an object setAge(20) is created whose value 20 is get printed as an output by getAge().

c) Inheritance

Inheritance in C++ is a feature that allows the inherit the characteristics of the Base class or parent class into the subclass or child class in a program. It also provides code reusability in C++.

Now let’s understand the inheritance with the help of an example in C++

Example:

Output:

Explanation: The code shows how the inheritance concept works in a C++ program as a Dog class inherits features from the Animal class in the code since the Dog class does not define its own sound() method in the program.

d) Polymorphism 

Polymorphism is a feature in C++ that helps functions to have multiple forms. Also there are two types of polymorphism: Compile-time polymorphism and Runtime polymorphism.

Examples: 

1. Compile-time Polymorphism (Function Overloading):

Output:

Explanation: The code shows how the compile-time polymorphism works in a C++ program as the add() method is defined two times in the program one for the integer and the other for the double, based on the types, and the std::cout prints the sum of both the data types separately to the console.

2. Runtime Polymorphism (Method Overriding):

Output:

Explanation: The code shows how the runtime polymorphism works in a C++ program as the show() function in the Parent class is declared as a virtual function that calls p -> show() on a Child object with an overridden version.

6. Memory Management

C++ supports manual memory management allocation and deallocation using new and delete operators.

Example:

Output:

10

Explanation: The code shows how the memory management concept works in a C++ program as memory is allocated dynamically for an integer with the value of 10 and will be printed using the *ptr, and then the memory is freed using the delete to avoid memory leaks.

7. Standard Template Library (STL)

STL in C++ provides predefined templates for common programming tasks.

STL Components:

Example:

Output:

30

Explanation: The code shows how the STL library can be used in a C++ program as a vector container with integer values 10, 20, and 30 is initialized which adds the value 40 using push_back() and then prints the element 30 at index 2.

Why You Should Learn C++?

• As the introduction makes clear, C++ is a powerful and high-performance language that can be used for real-time systems, competitive programming, game development, and system programming. 
• Also, it has low-level memory control and high-level object-oriented capabilities making it ideal for software that is scalable and effective. 
• Gaining knowledge of C++ will give you a strong foundation in memory management, multi-threading, and data structures, which are essential for performance optimization. 
• Also for careers in software development, cybersecurity, and embedded systems, as well as for a seamless transition into languages like Java and Python, its adaptability, flexibility, and cross-platform compatibility make it worthwhile to learn. 

Applications of C++

Below are a few applications of C++, as it is widely used across different domains due to its flexibility and efficiency:

1. Game engines like Unreal Engine use C++ due to its high efficiency and memory management features. 
2. In the development of operating systems, drivers, and embedded system software C++ is used.
3. C++ is used by banks and other financial institutions to run high-frequency trading algorithms, manage risk as well as process transactions. 
4. To make sure that data handling is fast and reliable, popular databases such as MySQL are built using C++ programming. 
5. Due to its speed and scalability, C++ enhances performance in cloud platforms and distributed systems. 
6. Scientists and engineers use C ++ in their applications as it can handle complex calculations and engineering problems. 
7. For high performance that is required in real-time processing in embedded systems, robotics, and automotive software use C++. 
8. C ++ is used inside your browser as both Chrome and Firefox use it for their rendering engines. 
9. Financial systems work effectively because of the advanced banking software programs that use C++. 
10. A lot of libraries use the C++ programming language for their computational efficiency, such as TensorFlow and OpenCV. 
11. Security tools, encryption technologies, and network protection software are made with C++.

Best Practices for C++ Programming

1. You must use the smart pointers such as std::unique_ptr and std::shared_ptr in C++ instead of using the raw pointers.
2. You should use stack allocation to minimize heap allocations and also avoid the use of new and delete operators.
3. You should avoid making unnecessary copies of the objects by using the std::move semantics and pass by constant reference.
4. Always enable the compiler optimizations for the improvement in performance.
5. You must optimize the code with loops and data structures in C++ using the std::vector over the std::list for better cache locality.
6. Always avoid excessive concatenation and use the std::string_view for proper string handling.
7. You can use the std::thread for implementing multi-threading in the C++ programs.
8. You should always analyze the performance of your C++ programs using tools such as gprof, Valgrind, or perf.

C++ vs Other Programming Languages

Conclusion

With this, we have completed discussing the C++ Introduction, we learned that C++ is one of the most powerful and versatile programming languages which combines high performance, memory management, and object-oriented programming features. You can use it in different domains such as game development, embedded systems, finance, and artificial intelligence. So, by understanding C++ programming language with its features, advantages, disadvantages, uses, core concepts, and best practices, you can easily write and develop an efficient application using C++.

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