C++ chapter 2

🟩 Chapter 2: Data Types, Variables, and Operators

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🔹 1. Tokens in C++

Smallest building blocks:

• Keywords – reserved words (e.g., int, class, if)
• Identifiers – names for variables/functions
• Literals – constants (10, 'A', "Hello")
• Operators – symbols that perform operations
• Punctuators – ;, {}, [], ()

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🔹 2. Data Types

Type	Keyword	Example
Integer	int	10
Floating	float	3.14
Double	double	9.81
Character	char	‘A’
Boolean	bool	true / false
Void	void	—

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🔹 3. Variables

Used to store data temporarily.
Syntax:

int age = 18;
char grade = 'A';

Rules:

• Must start with letter or underscore
• No spaces or special symbols
• Case-sensitive

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🔹 4. Constants

Values that cannot be changed:

const float PI = 3.14;

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🔹 5. Operators

A. Arithmetic

+, -, *, /, %

B. Relational

==, !=, >, <, >=, <=

C. Logical

&&, ||, !

D. Assignment

=, +=, -=, *=, /=

E. Increment/Decrement

++, --

F. Conditional (Ternary)

(a > b) ? a : b;

G. Bitwise

&, |, ^, ~, <<, >>

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🔹 6. Type Casting

Convert data from one type to another.

float a = (float)5 / 2;

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🔹 7. Input/Output in C++

#include <iostream>
using namespace std;

int main() {
    int age;
    cout << "Enter your age: ";
    cin >> age;
    cout << "You entered: " << age;
    return 0;
}

• cin → input
• cout → output