//求立方体的体积、表面积(c++)
#include
#include
#define COST 20
using namespace std;
class tiji
{
private:
double length,width,height;
public:
tiji(){};
tiji(double l, double w, double h)	//构造函数的形参,给私有变量赋值
{
length =l;
width =w;
height =h;
}
double changft_tiji()
{
//double v;
double v=length*width*height;
return v;
}
double biao_area()
{
double s;
s=2*(length*height+length*width+width*height);
return s;
}
double repaie()
{
double ss ;
ss = 2*(length*height+length*width+width*height)-length*width;
return ss;
}
void input();	//声明
};
void tiji::input()
{
cin>>length>>width>>height;
}
void menu()
{
cout