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C Examples

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Syntax

Create a simple "Hello World" program

Syntax Explained

Output/Print

Use printf to print text Using many printf functions Insert a new line with \n

Output Explained

Comments

Single-line comment before a line of code Single-line comment at the end of a line of code Multi-line comment

Comments Explained

Variables

Create an integer variable and print it Combine both text and a variable Change/overwrite variable values Add a variable to another variable Declare many variables of the same type with a comma-separated list Assign the same value to multiple variables of the same type Real-life variables example

Variables Explained

Data Types and Format Specifiers

A demonstration of different data types and format specifiers Set decimal precision for floating point values Implicit/automatically conversion - convert an int to a float Explicit/manually conversion - convert an int to a float

Data Types and Format Specifiers Explained

Constants

Create a constant variable Good practice - use uppercase letters when declaring constants

Constants Explained

Operators

Addition operator Subtraction operator Division operator Modulus operator Increment operator Decrement operator Assignment operator Addition assignment operator Comparison operator Logical operators Using the "sizeof" operator to get the memory size of different variables

Operators Explained

Booleans

Create boolean variables Compare two values Compare two variables Compare two boolean variables Real-life example

Variables Explained

If...Else (Conditions)

The if statement The else statement The else if statement Short hand if...else

If...Else Explained

Switch

The switch statement The switch statement with a default keyword

Switch Explained

Loops

While loop Do while loop For loop Nested loop Break a loop Continue a loop

Loops Explained

Arrays

Create and access an array Change an array element Loop through an array Two-dimensional array Change elements in a two-dimensional array Loop through a two-dimensional array

Arrays Explained

Strings

Create a string Another way to create a string Access string characters Change string characters Loop through a string Special characters in a string Get the length of a string Concatenate strings Copy strings Compare strings

Strings Explained

User Input

Input a number and print the result Input a string and print the result

User Input Explained

Memory Address/References

Get the memory address of a variable

Memory Address Explained

Pointers

Create a pointer variable Get the value of a variable with the dereference operator * Access an array with pointers Loop through an array using pointers

Pointers Explained

Functions

Create and call a function Call a function multiple times Function declaration and definition Parameters and arguments Multiple parameters Pass arrays as function parameters Return value Return the sum of two parameters Local scope Global scope Recursion (make a function call itself) Use a math function to get the square root of a number

Functions Explained

Files

Create a file Write to a file Append/add content to a file Read the first line of a file Read all lines of a file Good practice when reading files

Files Explained

Structures

Access a structure Create multiple structure variables with different values String in structure Simpler Syntax (shorthand) Copy structure values Modify values Real Life Example

Structures Explained

Enums

Create an enum variable and assign a value to it Change the value of enum items Change the value of a specific enum item Enum in a switch statement

Enums Explained

Memory Management

Get the size of different data types Dynamically allocate memory to store an array of integers Read from and write to dynamic memory Reallocate memory Reallocate memory and check for errors Deallocate (free) memory Real-life memory management example

Enums Explained

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