return

  The return statement causes a return from a function, with or
  without a  return value. 
  Syntax:

      return ;
      return expression ;

 The return value is undefined if not specified in a return
 statement.  If an expression is specified in the return statement,
 it is evaluated and the value is returned to the calling function;
 the value is converted, if necessary, to the type with which the
 called function was declared.  If a function does not have a return
 statement, the effect (on reaching the end of the function) is the
 same as with a return statement that does not specify an
 expression.  Functions declared as void may not contain return
 statements specifying an expression.