Placeholder function parameter

. 1 #include <bits / STDC ++ H.>
 2  the using  namespace STD;
 . 3  
. 4  void FUNC ( int A, int ) // function positional parameters, only the parameter type is not the parameter name 
. 5  {
 . 6      COUT << " the Hello World \ n- " ;
 . 7  }
 . 8  int main ()
 . 9  {
 10      FUNC ( 10 , 10 );
 . 11      return  0 ;
 12 is }

What is supplemented with behind