（1）以下程序中f()函数的形式参数有        个
# include <iostream.h>
f ( int b[] , int n )
{
 int i , r=1 ;
 for (i=0; i <= n; i++ )  r = r * b[i] ;
 return r ;
}
void main ()
{
 int x , a[ ] = {2,3,4,5,6,7,8,9} ;
 x=f (a , 3);
 cout << x << endl ;
}