ALX LOW LEVEL PROGRAMMING

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Table of Contents

• Author Details
• Projects
  • 0. 0x00. C - Hello, World
  • 1. 0x01. C - Variables, if, else, while
  • 2. 0x02. C - Functions, nested loops
  • 3. 0x03. C - Debugging
  • 4. 0x04. C - More functions, more nested loops
  • 5. 0x05. C - Pointers, arrays and strings
  • 6. 0x06. C - More pointers, arrays and strings
  • 7. 0x07. C - Even more pointers, arrays and strings
  • 8. 0x08. C - Recursion
  • 9. 0x09. C - Static libraries
  • 10. 0x0A. C - argc, argv
  • 11. 0x0B. C - malloc, free
  • 12. 0x0C. C - More malloc, free
  • 13. 0x0D. C - Preprocessor
  • 14. 0x0E. C - Structures, typedef
  • 15. 0x0F. C - Function pointers
  • 16. 0x10. C - Variadic functions
  • 17. 0x11. C - printf
  • 18. 0x12. C - Singly linked lists
  • 19. 0x13. C - More singly linked lists
  • 20. 0x14. C - Bit manipulation
  • 21. 0x15. C - File I/O
  • 22. 0x16. C - Simple Shell
  • 23. 0x17. C - Doubly linked lists
  • 24. 0x18. C - Dynamic libraries
  • 25. 0x19. C - Stacks, Queues - LIFO, FIFO (monty)
  • 26. 0x1A. C - Hash tables
  • 27. 0x1B. C - Sorting algorithms & Big O
  • 28. 0x1C. C - Makefiles
  • 29. 0x1D. C - Binary trees
  • 30. 0x1E. C - Search Algorithms
  • 31.

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Author Details

• Dean Robin Otsyeno - [email protected]

Project

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Table of Contents

0. 0x00. C - Hello, World

• Why C programming is awesome
• Who invented C
• Who are Dennis Ritchie, Brian Kernighan and Linus Torvalds
• What happens when you type gcc main.c
• What is an entry point
• What is main
• How to print text using printf, puts and putchar
• How to get the size of a specific type using the unary operator sizeof
• How to compile using gcc
• What is the default program name when compiling with gcc
• What is the official C coding style and how to check your code with betty-style
• How to find the right header to include in your source code when using a standard library function
• How does the main function influence the return value of the program

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1. 0x01. C - Variables, if, else, while

• What are the arithmetic operators and how to use them
• What are the logical operators (sometimes called boolean operators) and how to use them
• What the the relational operators and how to use them
• What values are considered TRUE and FALSE in C
• What are the boolean operators and how to use them
• How to use the if, if ... else statements
• How to use comments
• How to declare variables of types char, int, unsigned int
• How to assign values to variables
• How to print the values of variables of type char, int, unsigned int with printf
• How to use the while loop
• How to use variables with the while loop
• How to print variables using printf
• What is the ASCII character set
• What are the purpose of the gcc flags -m32 and -m64

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2. 0x02. C - Functions, nested loops

• What are nested loops and how to use them
• What is a function and how do you use functions
• What is the difference between a declaration and a definition of a function
• What is a prototype
• Scope of variables
• What are the gcc flags -Wall -Werror -pedantic -Wextra -std=gnu89
• What are header files and how to to use them with #include

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3. 0x03. C - Debugging

• What is debugging
• What are some methods of debugging manually
• How to read the error messages

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4. 0x04. C - More functions, more nested loops

• What are nested loops and how to use them
• What is a function and how do you use functions
• What is the difference between a declaration and a definition of a function
• What is a prototype
• Scope of variables
• What are the gcc flags -Wall -Werror -pedantic -Wextra -std=gnu89
• What are header files and how to to use them with #include

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5. 0x05. C - Pointers, arrays and strings

• What are pointers and how to use them
• What are arrays and how to use them
• What are the differences between pointers and arrays
• How to use strings and how to manipulate them
• Scope of variables

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6. 0x06. C - More pointers, arrays and strings

• What are pointers and how to use them
• What are arrays and how to use them
• What are the differences between pointers and arrays
• How to use strings and how to manipulate them
• Scope of variables

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7. 0x07. C - Even more pointers, arrays and strings

• What are pointers to pointers and how to use them
• What are multidimensional arrays and how to use them
• What are the most common C standard library functions to manipulate strings

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8. 0x08. C - Recursion

• What is recursion
• How to implement recursion
• In what situations you should implement recursion
• In what situations you shouldn’t implement recursion

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9. 0x09. C - Static libraries

• What is a static library, how does it work, how to create one, and how to use it
• Basic usage of ar, ranlib, nm

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10. 0x0A. C - argc, argv

• How to use arguments passed to your program
• What are two prototypes of main that you know of, and in which case do you use one or the other
• How to use __attribute__((unused)) or (void) to compile functions with unused variables or parameters

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11. 0x0B. C - malloc, free

• What is the difference between automatic and dynamic allocation
• What is malloc and free and how to use them
• Why and when use malloc
• How to use valgrind to check for memory leak

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12. 0x0C. C - More malloc, free

• How to use the exit function
• What are the functions calloc and realloc from the standard library and how to use them

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13. 0x0D. C - Preprocessor

• What are macros and how to use them
• What are the most common predefined macros
• How to include guard your header files

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14. 0x0E. C - Structures, typedef

• What are structures, when, why and how to use them
• How to use typedef

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15. 0x0F. C - Function pointers

• What are function pointers and how to use them
• What does a function pointer exactly hold
• Where does a function pointer point to in the virtual memory

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16. 0x10. C - Variadic functions

• What are variadic functions
• How to use va_start, va_arg and va_end macros
• Why and how to use the const type qualifier

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17. 0x11. C - printf

• The printf function is a very important and versatile function in the C programming language and being about to create your custom version of it will go a long way to enhance your understanding of the language.
• The first secret to being able to complete this project successfully is to first get a solid understanding of the printf function itself, how it works and all the different ways in which it can be used.

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18. 0x12. C - Singly linked lists

• When and why using linked lists vs arrays
• How to build and use linked lists

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19. 0x13. C - More singly linked lists

• How to use linked lists
• Start to look for the right source of information without too much help

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20. 0x14. C - Bit manipulation

• Look for the right source of information without too much help
• How to manipulate bits and use bitwise operators

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21. 0x15. C - File I/O

• Look for the right source of information online
• How to create, open, close, read and write files
• What are file descriptors
• What are the 3 standard file descriptors, what are their purpose and what are their POSIX names
• How to use the I/O system calls open, close, read and write
• What are and how to use the flags O_RDONLY, O_WRONLY, O_RDWR
• What are file permissions, and how to set them when creating a file with the open system call
• What is a system call
• What is the difference between a function and a system call

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22. 0x16. C - Simple Shell

• The famous Simple Shell project. This is one of the most anticipated project and also one that will challenge you a lot about everything you have learn so far:

  • Basics of programming
  • Basics of C
  • Basics of thinking like an engineer
  • Group work
  • and Learning how to learn

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23. 0x17. C - Doubly linked lists

• What is a doubly linked list
• How to use doubly linked lists
• Understand and know how to implement the various operations (deletion, insertion, etc) with doubly linked lists
• Start to look for the right source of information without too much help

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24. 0x18-dynamic_libraries

• What is a dynamic library, how does it work, how to create one, and how to use it
• What is the environment variable $LD_LIBRARY_PATH and how to use it
• What are the differences between static and shared libraries
• Basic usage nm, ldd, ldconfig

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25. 0x19. C - Stacks, Queues - LIFO, FIFO (monty)

• What do LIFO and FIFO mean
• What is a stack, and when to use it
• What is a queue, and when to use it
• What are the common implementations of stacks and queues
• What are the most common use cases of stacks and queues
• What is the proper way to use global variables

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26. 0x1A. C - Hash tables

• What is a hash function
• What makes a good hash function
• What is a hash table, how do they work and how to use them
• What is a collision and what are the main ways of dealing with collisions in the context of a hash table
• What are the advantages and drawbacks of using hash tables
• What are the most common use cases of hash tables

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27. 0x1B. C - Sorting algorithms & Big O

• At least four different sorting algorithms
• What is the Big O notation, and how to evaluate the time complexity of an algorithm
• How to select the best sorting algorithm for a given input
• What is a stable sorting algorithm

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28. 0x1C. C - Makefiles

• What are make, Makefiles
• When, why and how to use Makefiles
• What are rules and how to set and use them
• What are explicit and implicit rules
• What are the most common / useful rules
• What are variables and how to set and use them

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29. 0x1D. C - Binary trees

• What is a binary tree
• What is the difference between a binary tree and a Binary Search Tree
• What is the possible gain in terms of time complexity compared to linked lists
• What are the depth, the height, the size of a binary tree
• What are the different traversal methods to go through a binary tree
• What is a complete, a full, a perfect, a balanced binary tree

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30. 0x1E. C - Search Algorithms

• What is a search algorithm
• What is a linear search
• What is a binary search
• What is the best search algorithm to use depending on your needs

More Info

• You will be asked to write files containing big O notations. Please use this format:
  • O(1)
  • O(n)
  • O(n!)
  • n*m -> O(nm)
  • n square -> O(n^2)
  • sqrt n -> O(sqrt(n))
  • log(n) -> O(log(n))
  • n * log(n) -> O(nlog(n))
  • …

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_{Dean Robin Otsyeno - [email protected]}