Introduction to C Programming

Programming Steps

• Step 1: Write the Source Code - Use a text editor (like Notepad++) or an IDE (like CodeBlocks) to input source code.
• Step 2: Build Executable Code - Compile and link the source code into an executable file (e.g., "Program1.exe") using the IDE build function.
• Step 3: Run Executable Code - Execute the program by using the "Run" button in the IDE.

C Terminology and Syntax

• Case Sensitivity - C is case sensitive; 'ROBO', 'Robo', and 'robo' are treated as distinct identifiers.
• Comments - Multi-line comments begin with /* and end with */, while single-line comments start with // and end at the line's end; both are ignored by the compiler.
• Statements - Each programming statement must end with a semi-colon (;).
• Preprocessor Directives - #include is used for including header files and does not end with a semi-colon; they are processed before compilation.

Header Files

• Purpose - Header files contain function definitions and variable declarations.
• File Inclusion - Use angle brackets < > for system headers (e.g., <string.h>) and double quotes " " for user-defined headers to specify search directories.

Block Definition

• Block - A group of statements enclosed in braces { }, treated as a single unit by the compiler.

Basic Arithmetic Operators

• Integer Division - Yields an integer result; e.g., 7 / 4 results in 1.
• Remainder Operator (%) - Returns the remainder after integer division; e.g., 7 % 4 yields 3.

Program Structure

• Definition - A program consists of sequentially executed programming statements.
• Class Practice Exercises - Include tasks such as printing letters, prompting for integers, and calculating sums or products.

Data Types

• Basic Data Types - Include int, char, float, and double. Examples:
  • int length;
  • char day;
  • float x;
  • double electron_mass;

Specifiers and Variable Naming

• Naming Rules - Identifiers can start with a letter or underscore, using lowercase for variables and uppercase for constants.
• Reserved Keywords - Include keywords like int, char, if, else, which have special significance in C.

Constants in C

• Definition - Constants are defined using the #define preprocessor directive (e.g., #define PI 3.14159).

Input Functions

• Getch() and Getche() - getch() reads a character without displaying it, while getche() echoes the character to the screen.

Control Statements

• Switch Statement - Facilitates multi-selection control flow using case labels for different outcomes; can include a default option.
• Goto Statement - Allows jumping to a specific label in the code, potentially altering execution flow.

Loop Statements

• Do…While Loop - Executes the loop body at least once, checking the loop condition afterward.

Pointer Syntax

• Pointer Declaration - Syntax is data_type *var_name; (e.g., int *p;).
• Pointer Operations - Pointers store memory addresses; use & to get an address and * to access the pointed value.

Mapping Function

• Map() Function - Maps a number from one range to another without constraining the value within limits; useful for adjusting ranges including negatives.