> #include <iostream.h>
> #include <math.h>
> #include <iomanip.h>
> void main ()
> {
> 	int num,i,j;
> 	double sum,tmp;
> 	cin>>num;
> 	double *ptr=new double [num];
> 	
> 	for ( i=0;i<num;i++ )
> 		cin>>ptr[i];
> 	
> 	for ( i=0;i<num;i++ )//to sort;
> 	{
> 		for ( j=i;j<num;j++ )
> 		{
> 			if ( ptr[j]>ptr[i] )
> 			{
> 				tmp=ptr[j];
> 				ptr[j]=ptr[i];
> 				ptr[i]=tmp;
> 			}
> 		}
> 	}
> 
> 	sum=pow ( ptr[0],1 / pow ( 2, num-1 ) );
> 
> 	for ( i=1;i<num;i++ )
> 	{
> 			sum*=pow ( pow ( ptr[i],pow( 2,i-1 ) ),1 / pow ( 2, num-1 ) );
> 	}
> 
> 	sum *= pow ( pow ( 2,  pow( 2,num ) -2 ),1/pow ( 2,num-1 ) );
> 
> 	cout<<setiosflags(ios::fixed)<<setprecision(3)<<sum<<endl;
> }

• Re:你这不折腾嘛，还要算通项出来，递推着做不行吗？ (11) xd 2005-05-24 17:45:09