A function definition, also known as function implementation shall include the following elements

1. function name;

2. function type;

3. list of parameters;

4. local variable declarations;

5. function statements; and

6. a return statement.

All the six elements are grouped two parts, namely,

♦ function header (First three elements);and

♦ function body (Second three elements).

A general format of a function definition to implement these two parts is given below

function_type function_name(parameter list)
local variable declaration;
executable statement1;
executable statement2;
. . . . .
. . . . .
return statement;

The first line function_type function_name(paramreter list) is known as the function header and the statements within the opening and closing braces constitute the function body, which is a compound statement.

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