Part 6 | Functions and Type of Functions | C Programming Malayalam Tutorial

Introduction

This tutorial focuses on functions in C programming, detailing their types and applications. Understanding functions is crucial for writing efficient and organized code, which is essential for any aspiring programmer. In this guide, we'll explore various types of functions, their parameters, return values, and practical coding examples.

Step 1: Understanding Functions

• Definition: A function is a block of code that performs a specific task. It is reusable and can be called multiple times within a program.
• Benefits:
  • Promotes code reusability.
  • Enhances readability and maintainability.
  • Allows for easier debugging.

Step 2: Types of Functions

1. Built-in Functions: Provided by the C standard library, such as printf() and scanf().
2. User-defined Functions: Created by the programmer to perform specific tasks.

Step 3: Function Components

• Function Declaration: Specifies the function's name, return type, and parameters.

  return_type function_name(parameter_type parameter_name);
  

• Function Definition: Contains the actual code that executes when the function is called.

  return_type function_name(parameter_type parameter_name) {
      // code to execute
  }
  

• Function Call: Invokes the function to execute its code.

  function_name(argument);
  

Step 4: Function Parameters and Arguments

• Parameters: Variables in the function declaration that accept values when the function is called.
• Arguments: Actual values passed to the function when it is called.
• Example:

  void display(int num) {
      printf("Number: %d\n", num);
  }
  

  • Call it using display(5);.

Step 5: Return Values

• Functions can return values using the return statement.
• Specify the return type in the function declaration.
• Example:

  int add(int a, int b) {
      return a + b;
  }
  

  • Call it and capture the return value:

  int result = add(3, 4);
  

Step 6: Types of Functions by Return and Argument

1. Function without Arguments and without Return Value:

   void greet() {
       printf("Hello, World!\n");
   }
   

2. Function with Arguments and without Return Value:

   void multiply(int a, int b) {
       printf("Product: %d\n", a * b);
   }
   

3. Function with Arguments and with Return Value:

   int subtract(int a, int b) {
       return a - b;
   }
   

4. Function without Arguments and with Return Value:

   int getRandomNumber() {
       return rand() % 100; // Returns a random number between 0 and 99
   }
   

Step 7: Pointers in Functions

• A pointer is a variable that stores the address of another variable.
• Passing pointers to functions allows direct manipulation of variables outside the function scope.
• Example:

  void increment(int *p) {
      (*p)++;
  }
  

Conclusion

Functions are a fundamental concept in C programming that help organize code and improve reusability. Understanding the types of functions, how to define them, and how to work with parameters and return values is essential for effective programming. As a next step, practice writing different types of functions and experiment with passing parameters and using return values to solidify your understanding.