#2 Understanding Variables, Input and Output: C++ and DSA

Bilal Sadiq — Thu, 07 Dec 2023 03:30:48 +0000

Last blog we studied the introduction to C++. In this blog post, we'll be studying about variables, how to take input from the user and how to dispaly the output and how they form the building blocks of C++ progrms.

What are variables?

Variables are conainers that hold data in a program. they act as placeholders for storing information that can be manipulated and used through out the program's execution. In C++, variables must be declared beforethey are used. A declaration specifies the data type of the variable and the name of the variable.
Syntax and examples for variable declaration:

Once the variables are declared you can assign values to it using assignment operator "=":

Beside assigning values to the variables manually, one can take them as input from the user, which is discussed below.

Input in C++:

Getting input from the user is a basic requirement in many programs. This can be done using "cin" stream available in C++.
To get input from the user you need to include the header file "isotream" in your program as shown below :

Example of taking input using "cin" stream :

This will show the Output as:

In this example, the program prompts the user to enter marks, reads the input using "cin", and then displays the entered value using "cout".

Output in C++:

Output in C++ is achieved using the cout stream. It is used to display information to the console.

Example demostrating Output in C++:

Output from the above code:

In this example, the program outputs the values of variables marks, cgpa, and grade to the console.

This was all for today. Next we will be seeing the Operators in C++.
Happy Coding!

#1 Introduction: C++ and DSA

Bilal Sadiq — Fri, 01 Dec 2023 03:02:21 +0000

Welcome to the exciting world of C++ programming! Whether you're a coding enthusiast or a newcomer to the realm of programming languages, C++ is a versatile and powerful language that has stood the test of time. In this blog post, we'll embark on a journey to explore the basics of C++, its history, and why it continues to be a go-to language for developers around the globe.

What is C++?

C++ is a general-purpose programming language that was created as an extension of the C programming language. Developed by Bjarne Stroustrup in the early 1980s, C++ was designed with the goal of adding object-oriented programming features to C, without sacrificing the efficiency and low-level access that C provided.

Features of C++

1. Object Oriented Programming (OOP) :
C++ supports the core principles of OOP, including
encapsulation, inheritance, and polymorphism. These features
allow developers to organize and structure their code in a
modular and reusable way.

2. Efficiency :
C++ provides low-level access to memory, making it suitable
for system-level programming and resource-constrained
environments. This level of control over memory makes C++ a
preferred choice for performance-critical applications.

3. Standard Template Library :
The STL is a treasure trove of pre-built classes and
functions that expedite development by providing generic
implementations of common algorithms and data structures.

4. Portability :
C++ programs can be compiled to run on different platforms
without modification. This portability makes it an excellent
choice for developing cross-platform applications.

Getting Started with C++

To start coding in C++, you'll need a compiler and an integrted
development environment. We'll be using Microsoft Visual
Studio Code.
You can download the VS Code from google by simply typing VS
Code download and by clicking the first link that appears after
search.

We'll be writing the first "Hello World!" program.
You need to create a file with extension .cpp and write the
following code :

After Writing the above code just simply hit run button on top
right corner and you will see the output as:

Congragulations! you have written your first program in C++.

Now let's talk about the program and it's structure :

The "#include using namespace std;" is the header
file you need to include in every C++ program.
Next is the function int main(), this is the main function, you
need to write your code in this main function.
We'll be discussing more about functions later.

Thanks,
Happy coding!

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