Concepts related to a function

The process of writing a function in C++ is very simple. Actually it consists of the following parts :

• Function header
• Function body

Syntax

The syntax of writing a function is as follows:

return-type function-name(parameters)

{

statement(s);

}

Function header

The first line of a function definition is known as a function header(function definition will be discussed later in this blog).

Its syntax is as follows:

Syntax

return-type function-name(parameters)

Function Body

The set of statement(s) written inside curly braces are known as function body. These are actually the statement(s) that are executed inside the function.

Function declaration

Function declaration is also known as function signature or function prototype.Remember that it ends with a semi colon. It tells the compiler about the structure of the function to be used in the program. It is written before the main( ) body.Its syntax is as follows :

Syntax

return-type function-name(parameters)

Example

void display( )

Function definition

A set of statements that actually explains what a function does is called a function. Remember that function definition can be written at the following places:

• Before main( ) function
• After main( ) function
• In a separate file

Syntax

return-type function-name(parameters)

{

statement(s);

}

Example

void display( )

{

cout<<"Hello world";

}