程序代码：

#ifndef STOCK_h_
#define STOCK_H_
#include<string>

//class declaration
class Stock
{
private://not indeed
        std::string company;
    long shares;
    double share_val;
    double total_val;
    void set_tot()
    {
        total_val = shares*share_val;
    }
public:
    void acquire(const std::string &co, long n, double pr);
    void buy(long num, double price);
    void sell(long num, double price);
    void update(double price);
    void show();
};
#endif

程序代码：

#include<iostream>
#include"stock.h"
void Stock::acquire(const std::string &co, long n, double pr)
{
    company = co;
    if (n < 0)
    {
        std::cout << "Number of shares can't be negative; "
            << company << "Shares set to 0.\n";
        shares = 0;
    }
    else
        shares = n;
    share_val = pr;
    set_tot();
}
void Stock::buy(long num, double price)
{
    if (num < 0)
    {
        std::cout << "Number of shares can't be negative, "
            << "Transaction is abort.\n";
    }
    else
    {
        shares += num;
        share_val = price;
        set_tot();
    }
}
void Stock::sell(long num, double price)
{
    using namespace std;
    if (num < 0)
    {
        cout << "Number of shares can't be negative, "
            << "Transaction is abort.\n";
    }
    else if (num>shares)
    {
        cout << "You can'tsell more than you have! "
            << "Transaction is abort.\n";
    }
    else
    {
        shares -= num;
        share_val = price;
        set_tot();
    }
}
void Stock::update(double price)
{
    share_val = price;
    set_tot();
}
void Stock::show()
{
    std::cout << "Company: " << company
        << " Shares: " << shares << '\n'
        << " Shares Price:$ " << share_val
        << " Total Worth:$ " << total_val << '\n';
}

程序代码：

#include "stdafx.h"
#include<iostream>
#include"stock.h"


int _tmain(int argc, _TCHAR* argv[])
{
    Stock vital;
    vital.acquire("NanoSmart", 20, 12.50);
    vital.show();
    vital.buy(15, 18.125);
    vital.show();
    vital.sell(400, 20.00);
    vital.show();
    vital.buy(300000, 40.125);
    vital.show();
    vital.sell(300000, 0.125);
    vital.show();
    return 0;
}

int _tmain(int argc, _TCHAR* argv[])

程序代码：

//#include "stdafx.h"
#include<iostream>
#include"stock.h"


int main()
{
    Stock vital;
    vital.acquire("NanoSmart", 20, 12.50);
    vital.show();
    vital.buy(15, 18.125);
    vital.show();
    vital.sell(400, 20.00);
    vital.show();
    vital.buy(300000, 40.125);
    vital.show();
    vital.sell(300000, 0.125);
    vital.show();
    system("pause");
    return 0;
}