c++ - 如何将两个对象作为一个元素添加到 vector 中？

Question

我在这里写了一段代码来理解一个问题。该程序应该询问您要将多少个数字存储在一个名为 vNumbers 的 vector 中，然后继续创建一个长度为 iNumbers 的 vector (您选择的迭代次数)。然后，您将输入您的第一个数字，该数字将被推回到 vNumbers 中，然后询问您想要输入多少个字母(对于每个数字)，这些字母将存储在 vector vLetters 中。之后它应该打印出 vNumbers 和 vLetters 中的内容。我可以让程序接受 1 个字母代表 1 个数字，但我不能让它接受多个字母代表 1 个数字。例如，如果我这样做

Please enter how many numbers you'd like to add:

2

Please enter #1

100

how many letters would you like to add (for number 100)

2

Please enter a letter

A

Please enter a letter

B

Please enter #2

200

How many letters would you like to add (for number 200)

1

Please enter a letter

C

我应该得到这个

You have entered:

100 A B

200 C

相反，我得到的是这个，我不确定为什么。

100 AB

200 ABC

#include <iostream>
#include <string>
#include <cctype>
#include <vector>
#include <algorithm>
using namespace std;



int main()
{
    string sLetters, sLettersB, sLettersC, sLettersA, sNumbers;
    vector<string> vLetters, vNumbers;
    int iLetters, iNumbers;
    
    cout << "how many NUMBERS would you like to add? ";
    cin >> iNumbers;
    cin.ignore();
    for (int j = 0; j < iNumbers; j++)
    {
        cout << j + 1 << "# Enter number ";
        getline(cin, sNumbers);
        vNumbers.push_back(sNumbers);

        cout << "how many LETTERS would you like to add to " << j + 1 << "#? ";
        cin >> iLetters;
        cin.ignore();
        for (int i = 0; i < iLetters; i++)
        {
            cout << "Enter letter";
            getline(cin, sLettersA);
            sLetters += sLettersA;

        }
        vLetters.push_back(sLetters); // How ever many letters are in sLetters should be added to n-1 index # in vector vLetters
    }
    for (int x = 0; x < vLetters.size(); x++)
    {
        cout << vNumbers[x] << "\t \t" << vLetters[x] << endl;

        
    }
    return 0;
}

Answer 1

您的代码有错误。请参阅下面的评论

    for (int i = 0; i < iLetters; i++)
    {
        cout << "Enter letter";
        getline(cin, sLettersA);
        sLetters += sLettersA;  // sLetters is defined outside for loop and no space

    }

因此您可以在第一个 for 循环中定义 sLetters 或使用 clear()

    sLetters.clear();
    for (int i = 0; i < iLetters; i++)
    {
        cout << "Enter letter";
        getline(cin, sLettersA);
        sLetters += ' ' + sLettersA;
    }

或者删除第3行的sLetters，稍后再定义

    string sLetters;
    for (int i = 0; i < iLetters; i++)
    {
        cout << "Enter letter";
        getline(cin, sLettersA);
        sLetters += ' ' + sLettersA;  
    }