C++ 食物菜单(使用 do while 循环)

Question

我在运行这个程序时遇到问题:我试图让用户输入他们在菜单上的选择(A、B、C、D 或 E )，如果他们选择是 选项。如果没有，则直接计算总销售价格。但是每当我选择是时，它似乎重复显示菜单并且不显示选项。请帮助我是 c++

的新手

#include <iostream>
#include <iomanip>

using namespace std;

int main()
{

    double a = 5.99, b = 4.99, c = 4.99, d = 5.99, e = 9.99, totalprice;
    const double TAX = 0.13;
    int choice = 0;
    char (answer);

    do
    {

        cout << "\nGood day! Welcome to The Bakery! What would you like today?\n";
        cout << "\nMenu\n                                                        Price"<< endl;
        cout << "A: Earl Gray Tea and Biscuits  -                        $" << a << endl;
        cout << "B: Coffee and a blueberry scone -                       $" << b << endl;
        cout << "C: Espresso and a tea biscuit -                         $" << c << endl;
        cout << "D: Coffee and a Muffin-                                 $" << d << endl;
        cout << "E: The Assorted Tea, Scones, and Biscuits Platter-      $" << e << endl;

        cout << "\nAre there any addtional orders? 'Y' or 'N'\n" << endl;
        cin >> answer;
        if (answer == 'Y' || answer == 'y')

        {   //Display Choice

            cout << "\nYour choice?\n" << endl;
        }


         if (choice == 'A' || choice == 'a')
         {

            cout << "A: Earl Gray Tea and Biscuits" << a << endl;

        }


        if (choice == 'B' || choice == 'b')
        {

            cout << "B: Coffee and a blueberry scone" << b << endl;

        }


      if (choice == 'C' || choice == 'c')
        {

            cout << "A: Earl Gray Tea and Biscuits" << c << endl;

        }


         if (choice == 'D' || choice == 'd')
        {

            cout << "D: Coffee and a Muffin" << d << endl;

        }


        if (choice == 'E' || choice == 'e')
        {

            cout << "E: The Assorted Tea, Scones, and Biscuits Platter" << e << endl;

        }

        else if (answer == 'N' || answer == 'n')
        {
            cin >> totalprice;
            cout << "The final bill for today is ";
        }

        else //Displaying error message
        {
            cout << "Invalid input";
        }

    } while (answer != 'Y' && answer != 'y');

} 

Answer 1

变量choice应该是一个字符，你必须添加cin来接收choice的输入

#include <iostream>
#include <iomanip>

using namespace std;

int main()
{

    double a = 5.99, b = 4.99, c = 4.99, d = 5.99, e = 9.99, totalprice;
    const double TAX = 0.13;
    char choice;
    char answer;

    do
    {

        cout << "\nGood day! Welcome to The Bakery! What would you like today?\n";
        cout << "\nMenu\n                                                        Price"<< endl;
        cout << "A: Earl Gray Tea and Biscuits  -                        $" << a << endl;
        cout << "B: Coffee and a blueberry scone -                       $" << b << endl;
        cout << "C: Espresso and a tea biscuit -                         $" << c << endl;
        cout << "D: Coffee and a Muffin-                                 $" << d << endl;
        cout << "E: The Assorted Tea, Scones, and Biscuits Platter-      $" << e << endl;
cin >> choice;
        cout << "\nAre there any addtional orders? 'Y' or 'N'\n" << endl;
        cin >> answer;
        if (answer == 'Y' || answer == 'y')

        {   //Display Choice

            cout << "\nYour choice?\n" << endl;
        }


         if (choice == 'A' || choice == 'a')
         {

            cout << "A: Earl Gray Tea and Biscuits" << a << endl;

        }


        if (choice == 'B' || choice == 'b')
        {

            cout << "B: Coffee and a blueberry scone" << b << endl;

        }


      if (choice == 'C' || choice == 'c')
        {

            cout << "A: Earl Gray Tea and Biscuits" << c << endl;

        }


         if (choice == 'D' || choice == 'd')
        {

            cout << "D: Coffee and a Muffin" << d << endl;

        }


        if (choice == 'E' || choice == 'e')
        {

            cout << "E: The Assorted Tea, Scones, and Biscuits Platter" << e << endl;

        }

        else if (answer == 'N' || answer == 'n')
        {
            cin >> totalprice;
            cout << "The final bill for today is ";
        }

        else //Displaying error message
        {
            cout << "Invalid input";
        }

    } while (answer != 'Y' && answer != 'y');

}