题目概述:
编程:
#include< iostream>
using namespace std;
class Product
{
public:
Product(int n, int q, float p) :num(n), quantity(q), price§ {};
void total();//计算总售款和总件数
static float average();//求平均售价(静态数据成员函数)
static void display();//输出结果(静态数据成员函数)
private:
int num;//售货员号
int quantity;//售货件数
float price;//单价
static float discount;//折扣(静态数据成员)
static float sum;//总销售款(静态数据成员)
static int n;//总销售件数(静态数据成员)
};
void Product::total()
{
float rate = 1.0;
if (quantity > 10)
rate = rate * 0.98;
sum = sum + quantity * price * rate * (1 - discount);
n = n + quantity;
}
void Product::display()
{
cout << sum << " " << average() << endl;
}
float Product::average()
{
return (sum / n);
}
//公用静态数据必须在类外初始化
float Product::discount = 0.05;//折扣0.05
float Product::sum = 0;
int Product::n = 0;
int main()
{
Product Prod[3] = { Product(101,5,23.5),Product(102,12,24.56),Product(103,100,21.5) };
for (int i = 0; i < 3; i++)
{
Prod[i].total();
}
Product::display();
return 0;
}
上机实践: