FuNctioNs.

Functions are very useful in c++ because it is used for re-usability of code this means we write a statement at once then we call that statement number of times and from this way we never write whole code again and again. function are work with three statements.
  • function declaration 
  • function calling
  • fuction definition


syntax of function declaration:
datatype function(parameters);


consider example for function declaration.
void sum(int a,int b);


syntax of function calling:
function(parameters without datatype);


example:
sum(a,b);


syntax function definition:
datatype function(parameters)
{
statement;
}



example:
void sum(int a,int b)
{
int c;
c=a+b;
cout<<c;
}