Question

class GroceryItem {
private:
   /* … */
public:
   /* … */    
   // operator overloadings
   friend istream& operator>> (istream& is, GroceryItem* item);
   friend ostream& operator<< (ostream& os, GroceryItem* item);
};   
istream& operator>> (istream& is, GroceryItem* item) {
    is >> item->_brandName >>item->_productName;
    return is;
}    
ostream& operator<< (ostream& os, GroceryItem* item) {
    os << "\nBrand "<< item->_brandName << "  product " << item->_productName;
    return os;
}    
int main()
{
    // declare vector of items
    std::vector<GroceryItem*> items;

    //GroceryItem1
    GroceryItem* item1 = new GroceryItem();
    std::cin >> item1;
    items.push_back(item1);

    //GroceryItem2
    GroceryItem* item2 = new GroceryItem();
    std::cin >> item2;
    items.push_back(item2);

    //print and delete all pointers to avoid memory leak
    for (auto p : items) {
        std::cout << p;
        delete p;
    }

    return 0;
}

我跑了ERROR: Could not open requirements file: [Errno 2] No such file or directory: 'requirements.txt'，得到了以下内容：

pip install --up

Answer 1

通过运行pip install -r requirements.txt，您会指示pip安装路径为requirements.txt的文件中列出的软件包。确保执行Requirements File Format之后的执行文件夹（requirements.txt中有一个名为C:\Users\evaim的文件。

为什么cmd.exe安装pip安装-r requirements.txt

1 个答案: