c++ - 我的部分代码作为我的 if 语句的一部分被跳过

Question

所以我试图做一个计算器，我添加了一个部分，这样我就可以计算面积，首先我要求整数或几何数学，当我选择几何时，它跳过了我想要计算体积的问题。但是没有编译器错误。它在 " else if (choice == "geometry") {" 之后的所有内容，直到最后一行。任何人都知道如何修复。

    #include <iostream>
    #include <string>
    #include <cmath>
    using namespace std;

    int main()
    {
      string choice;
      cout << "choose integer or geometry\n";
      cin >> choice;
      if (choice == "integer") {
     double num1{ 0 };
     double num2{ 0 };
     cout << "pick a number\n";
     cin >> num1;
     cout << "pick another number\n";
     cin >> num2;
     string integerChoice;
     cout << "choose addition, subtraction, multipliction, or division\n";
     cin >> integerChoice;
     if (integerChoice == "addition") {
        cout << num1 << " + " << num2 << " is " << num1 + num2
            << '\n';
     }
     else if (integerChoice == "subtraction") {
        cout << num1 << " - " << num2 << " is " << num1 - num2
            << '\n';
     }
     else if (integerChoice == "multiplication") {
        cout << num1 << " * " << num2 << " is " << num1 * num2
            << '\n';
     }
     else if (integerChoice == "division") {
        cout << num1 << " / " << num2 << " is " << num1 / num2
            << '\n';
     }//integer is done
     }
      else if (choice == "geometry") {
    string geoChoice1;
    cout << "do you want to calculate volume, enter yes or no\n";
    cin >> geoChoice1;
    if (geoChoice1 == "yes") {
        cout << "choose retangular prism(incudes cubes), cone, or cylinder\n";

        string volumeChoice;
        cin >> volumeChoice;
        if (volumeChoice == "rectangular prism") {
            double recPrismLength{ 0 };
            double recPrismWidth{ 0 };
            double recPrismHeight{ 0 };
            cout << "Enter the length\n";
            cin >> recPrismLength;
            cout << "Enter the width\n";
            cin >> recPrismWidth;
            cout << "Enter the height\n";
            cin >> recPrismHeight;
            cout << recPrismLength << " * " << recPrismWidth << " * " << recPrismHeight << " is " <<
                recPrismLength * recPrismWidth * recPrismHeight << '\n';
        }
        else if (volumeChoice == "cylinder") {
            float cHeight;
            float cRadius;
            const double pi{ 3.14159265358979323846 };
            float cFormula{ pi * pow(2.0, cRadius) * cHeight };
            cout << "Enter the height of the cylinder\n";
            cin >> cHeight;
            cout << "Enter the radius of the cylinder\n";
            cin >> cRadius;
            cout << cFormula;


        }
        else if (geoChoice1 == "no") {

标签： c++visual-c++

Answer 1

固定代码：

#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
using namespace std;

std::string ToLower(std::string str) {
    std::transform(str.begin(), str.end(), str.begin(),
        [](unsigned char c) { return std::tolower(c); });
}

int main()
{
    string choice;
    cout << "choose integer or geometry\n";
    cin >> choice;
    if (choice == "integer") {
        double num1{ 0 };
        double num2{ 0 };
        cout << "pick a number\n";
        cin >> num1;
        cout << "pick another number\n";
        cin >> num2;
        string integerChoice;
        cout << "choose addition, subtraction, multipliction, or division\n";
        cin >> integerChoice;
        if (integerChoice == "addition") {
            cout << num1 << " + " << num2 << " is " << num1 + num2
                << '\n';
        }
        else if (integerChoice == "subtraction") {
            cout << num1 << " - " << num2 << " is " << num1 - num2
                << '\n';
        }
        else if (integerChoice == "multiplication") {
            cout << num1 << " * " << num2 << " is " << num1 * num2
                << '\n';
        }
        else if (integerChoice == "division") {
            cout << num1 << " / " << num2 << " is " << num1 / num2
                << '\n';
        }//integer is done
    }
    else if (choice == "geometry") {
        string geoChoice1;
        while (!(geoChoice1 == "yes" || geoChoice1 == "no"))
        cout << "do you want to calculate volume, enter yes or no\n";
        cin >> geoChoice1;
        ToLower(geoChoice1);
        if (geoChoice1 == "yes") {
            cout << "choose retangular prism(incudes cubes), cone, or cylinder\n";

            string volumeChoice;
            cin >> volumeChoice;
            ToLower(volumeChoice);
            if (volumeChoice == "rectangular prism") { //this will never be executed, as the >> operator skips whitespace, and therefore will only read "rectangular"
                //I will leave this for you to fix
                double recPrismLength{ 0 };
                double recPrismWidth{ 0 };
                double recPrismHeight{ 0 };
                cout << "Enter the length\n";
                cin >> recPrismLength;
                cout << "Enter the width\n";
                cin >> recPrismWidth;
                cout << "Enter the height\n";
                cin >> recPrismHeight;
                cout << recPrismLength << " * " << recPrismWidth << " * " << recPrismHeight << " is " <<
                    recPrismLength * recPrismWidth * recPrismHeight << '\n';
            }
            else if (volumeChoice == "cylinder") {
                float cHeight;
                float cRadius;
                const double pi{ 3.14159265358979323846 };
                double cFormula{ pi * pow(2.0, cRadius) * cHeight }; //this will always be the same, please note, because cHeight and cRadius are only filled after this function
                cout << "Enter the height of the cylinder\n";
                cin >> cHeight;
                cout << "Enter the radius of the cylinder\n";
                cin >> cRadius;
                cout << cFormula;
                break;
            }
        }
        else if (geoChoice1 == "no") break;
        else cout << "Please enter something I understand, either 'yes' or 'no'.\n";
    } //this was missing
} //this was missing

如果用户用大写 Y 输入“是”，您的代码没有考虑到。代码只会得出“是”不等于“是”的结论。我制作了一个函数，将您的输入转换为小写形式，然后对其进行评估，如果不是“是”或“否”，则要求用户再次输入。

还有一些其他错误我已发表评论，您将不得不修复。