Functions

• A function is a unit of code designed to perform a particular purpose or specific task.
• Function - It allows a programmer to organize a program and break down a certain program into a smaller, manageable, and reusable codes.
• A function can take input values, process them, and display or return an output.
• Types of Functions

  • User-Defined Functions - It is to create our own function based on our requirements.
  • Built-In Functions - These are built-in functions in C++ that are available to use, sucha as sqrt(), abs(), isdigit(), etc.
• Key Features of C++ Functions

  • Modularity
  • Reusability
  • Parameterization
  • Return Values
  • Built-in and User-defined
• Modularity

  • Functions help break a program into smaller, manageable, and logical parts (modules).
  • Each function performs a specific task, making the code easier to organize and debug.
• Reusability

  • Once a function is defined, it can be reused multiple times without rewriting the code.
  • This reduces redundancy and makes the code more efficient and easier to maintain.
• Parameterization

  • Functions can accept inputs (parameters) to operate on, making them flexible.
  • For example, a function can calculate the sum of different pairs of numbers based on arguments passed.
• Return Values

  • Functions can return a value to the caller after performing a task.
  • For instance, a function can return the result of a mathematical operation.
• Built-in and User-defined Functions

  • Built-in Functions: C++ provides several predefined functions, such as sqrt() for square root or cout for output.
  • User-defined Functions: Programmers can create their own functions to perform specific tasks.
• Function Declaration Syntax

  returnType functionName (parameter1, parameter2, ...){

  // function body

  }
• returnType - It specifies what type of value a function returns, such as int, void - a return type does not return any value.
• functionName - It is a identifier that is used to refer to the particular function in a program.
• parameters (optional) - List of values passed to a function.
• function body - It includes the programming statements that are used to perform some tasks.
• Calling a Function

  functionName (argument1, argument2, ...);
• argument (optional) - The values to be passed in the function.
• functionName - It is an identifier that is used to refer to the particular function in a program.