C++ Core Concepts Overview

Overview

This lecture covers the core concepts needed to get started in C++, from setting up your environment to basic syntax, variables, operators, control structures, arrays, functions, object-oriented programming, and more.

Why Learn C++ & Setup

• C++ is a fast, middle-level language used in graphics, embedded systems, and video game development.
• C++ balances human-readable code and machine-level control.
• You need a text editor (e.g., VS Code) and a compiler (e.g., GCC for Windows/Linux, Clang for Mac).
• IDEs like VS Code and Code Blocks provide helpful developer tools.

Writing Your First C++ Program

• Include header files with #include <iostream> for input/output operations.
• The program starts at the int main() function.
• Use std::cout to print output, ending statements with a semicolon.
• Use std::endl or \n for new line output.
• Comments start with // for single line, /* ... */ for multiline.

Variables & Data Types

• Variables represent data; declare with a data type (int, double, char, bool, string).
• Assignment can be combined with declaration: int x = 5;
• int stores whole numbers, double stores decimals, char stores single characters, bool is true/false, string stores text.
• Use std::cin to accept user input; use std::getline for input with spaces.

Constants & Namespaces

• const keyword makes variables read-only.
• Naming CONVENTION: constants are uppercase.
• Namespaces group entities and avoid naming conflicts; access with namespace::entity.

Typedefs & Type Aliases

• typedef and using create type aliases for improved readability.

Operators & Expressions

• Arithmetic operators: +, -, *, /, % (modulus).
• Use ++ and -- for increment/decrement, +=, -= for shorthand updates.
• Operator precedence: parentheses > multiplication/division > addition/subtraction.
• Type conversion (implicit/explicit) changes data types as needed.*

Control Structures

• if, else if, else for decision making.
• switch is efficient for multiple discrete cases, use break to exit cases.
• Ternary operator: condition ? expr1 : expr2;
• Logical operators: && (and), || (or), ! (not).

Loops

• while and do...while for repeating code under a condition.
• for loop for a set number of iterations.
• break exits a loop; continue skips an iteration.
• Nested loops allow for multi-level iteration (e.g., grids).

Arrays & Strings

• Arrays store multiple values of the same type, indexed from 0.
• Use sizeof(array)/sizeof(array[0]) to get array length.
• Iterate arrays with loops (for or range-based for).
• 2D arrays represent grids or matrices.
• Common string methods: .length(), .empty(), .clear(), .append(), .at(), .insert(), .find(), .erase().
• Use std::fill() to initialize array values.

Functions

• Functions group reusable code, may take parameters and return values.
• Overloaded functions share the same name but have different parameters.
• Pass by value copies arguments; pass by reference modifies originals.
• Use const for read-only parameters.

Pointers & Dynamic Memory

• Pointer is a variable that stores a memory address; use * for declaration and dereferencing.
• Null pointers (nullptr) indicate no assigned address.
• Use new to allocate dynamic memory and delete to free it.*

Object-Oriented Programming

• Classes define objects with attributes and methods.
• Constructors initialize object attributes, support overloading.
• Access modifiers (public, private) control visibility.
• Use getters and setters for encapsulation.
• Inheritance allows child classes to receive attributes/methods from parent classes.

Structs & Enums

• struct groups related variables (members) of different types.
• enum creates a set of named integer constants for fixed choices.

Other Concepts

• Random numbers: rand(), seeded with srand().
• Templates generalize functions for multiple data types.
• Search and sort algorithms can be implemented with arrays.
• Recursion is when a function calls itself for repetitive tasks.

Key Terms & Definitions

• Compiler — software that converts code to machine instructions.
• Namespace — a scope for identifiers to avoid naming conflicts.
• Pointer — a variable storing the address of another variable.
• Class — a blueprint for creating objects with attributes and methods.
• Constructor — special class function to initialize new objects.
• Getter/Setter — methods for reading/updating private attributes.
• Inheritance — a mechanism where one class derives from another.

Action Items / Next Steps

• Practice by writing simple programs using variables, loops, and functions.
• Create a class with a constructor, getter, and setter.
• Try implementing array search and sort functions.
• Review any assigned homework or exercises from the lecture.