C++ Programming

Chapter 2 — C++ Fundamentals: Variables, Types & I/O

📚 Chapter Overview

This chapter builds the foundation of C++ logic. You will learn how the computer stores data in memory using variables, the different types of data C++ can handle, and how to interact with the user via the console.

Learning Objectives:

2.1 Variables and Constants

Part 1 — Definition

A Variable is a named storage location in memory that holds a value. In C++, variables must be declared with a type. A Constant is a variable whose value cannot be changed once assigned, defined using the const keyword.

Part 2 — Syntax

int age = 20;
const float PI = 3.14;

Part 3 — Example

Problem: Store a student's marks and prevent them from being changed.

Main.cpp 
int marks = 85;
const int MAX_MARKS = 100;
cout << "Marks: " << marks << "/" << MAX_MARKS;

Output: Marks: 85/100

Part 4 — Video

Video: Coming Soon

2.2 Input and Output (cin/cout)

Part 1 — Definition

C++ uses Streams for I/O. cout (Character Output) displays data on the screen using the insertion operator (<<). cin (Character Input) reads data from the keyboard using the extraction operator (>>).

Part 2 — Syntax

cout << "Message";
cin >> variable;

Part 3 — Example

Problem: Ask for a user's age and display it back.

Main.cpp 
int userAge;
cout << "Enter your age: ";
cin >> userAge;
cout << "You are " << userAge << " years old.";

Part 4 — Video

Video: Coming Soon

🏆 Chapter Challenge

Challenge Objective

Build a "Rectangle Property Calculator" that takes inputs and performs calculations.

Requirements

Step-by-Step Process

  1. Declare float variables for L, W, A, P.
  2. Use cout to prompt the user.
  3. Use cin to store values.
  4. Apply the math formulas.
  5. Print the final results using endl for new lines.

Expected Deliverables

Solve in Compiler