Lecture: Introduction to Programming in C

Importance of Learning C

• C is a middle-level programming language developed in the 1970s.
• Bridges the gap between high-level languages (easier to work with, more abstract) and low-level languages (efficient, faster, closer to machine architecture).
• Influences most programming languages today; foundational concepts include variables, data types, loops, arrays, functions.
• Used in systems programming, databases, embedded systems.
• C is procedural, not object-oriented. Unlike C++, which is an extension of C.

Setting Up the Environment

• Integrated Development Environment (IDE): Recommended to use Visual Studio Code (VS Code).
• GNU Compiler Collection (GCC): Required to compile C code into machine code.
• Installation Instructions:
  • Download VS Code from code.visualstudio.com.
  • Install necessary extensions: C/C++ extension (IntelliSense) and Code Runner.
  • Configure the default build task in VS Code for C programming.
  • Verify GCC installation using command g++ --version.

Writing Your First C Program

• Include Standard Library: Use #include <stdio.h> for input/output functions.
• Main Function: Entry point of any C program, int main() { ... }.
• Print to Console: Use printf with format specifiers, e.g., %d for integers.
• Compile and Run:
  • Use command prompt for Windows or terminal for Mac/Linux.
  • Compile with gcc filename.c -o output and run with ./output.

Basic C Programming Concepts

• Variables and Data Types:
  • int, float, char, double, bool (include <stdbool.h> for booleans).
  • Declaration followed by initialization, e.g., int age = 21;.
• Operators:
  • Arithmetic: +, -, *, /, %.
  • Augmented Assignment: +=, -=, etc.
  • Logical: &&, ||, !.
• Control Structures:
  • If Statements: Conditional execution of code blocks.
  • Switch Statements: Handling multiple conditions.*

Functions and Prototypes

• Function Declaration: Define reusable code blocks with a return type and parameters, e.g., int add(int a, int b);.
• Function Prototypes: Declaration of functions before the main() to ensure correct usage.
• Return Statement: Functions can return values to the calling function.

Working with Arrays and Strings

• Arrays: Fixed-size collections of elements of the same type, accessed via indices.
• Strings: Arrays of characters, typically null-terminated.
• Two-Dimensional Arrays: Arrays of arrays, useful for matrices and grids.

File Handling

• Reading and Writing Files:
  • Use fopen(), fclose(), fprintf(), fgets() for file operations.
  • Modes: `