c++ - 从 C 入门学习。预期的表达式错误 Xcode

Question

我正在通过 C 入门学习 C++。我卡在这个问题的最后一部分 (1.6(p. 25))

Exercises Section 2.6.2 Exercise 2.41: Use your Sales_data class to rewrite the exercises in § 1.5.1 (p. 22), § 1.5.2 >(p. 24), and § 1.6 (p. 25). For now, you should define your Sales_data class in the same file >as your main function.

#include <iostream>
#include <string>

struct Sales_data 
{
    std::string Book_Name;
    unsigned Units_Sold = 0;
    double Revenue = 0.0;
};

int main()
{
    double price;
    Sales_data total;  // variable to hold data for the next transaction // read the first transaction and ensure that there are data to process
    if (std::cin >> total.Book_Name >> total.Units_Sold >> price) 
    {
        total.Revenue = total.Units_Sold * price;
        Sales_data trans; // variable to hold the running sum // read and process the remaining transactions
        while (std::cin >> trans.Book_Name >> trans.Units_Sold >> price) 
        {
            trans.Revenue = trans.Units_Sold*price;
            // if we're still processing the same book
            if (total.Book_Name == trans.Book_Name)
            {
                total.Units_Sold += trans.Units_Sold; // update the running 
                total.Revenue += trans.Revenue; // update the running 
            }
            else 
            {
            std::cout << total.Book_Name << total.Units_Sold << total.Revenue;
            **total.Book_Name = trans.Book_Name;**
            total.Units_Sold = trans.Units_Sold;
            **total.Revenue = trans.Revenue;**
            }
            **std::cout << total.Book_Name << total.Units_Sold << price << std::endl;** //print the last transaction 
        }
    }
    else 
    {
        // no input! warn the user
        std::cerr << "No data?!" << std::endl; 
        return -1; // indicate failure
    }
    return 0; 
}

哪里有 ** Xcode 一直告诉我预期的表达式..我不知道哪里出了问题请帮忙...

Answer 1

根据您对我的评论的回复，您在从电子书中复制一些代码时引入了一些奇怪的字符。当我用 gcc 复制和编译程序时，我收到如下错误 ( live example here ):

error: stray ‘\357’ in program

\357 是一个八进制转义序列。删除这些字符后，程序可以正常编译。