C++ cin 和 CTRL + Z 问题

我正在阅读《C++ Primer 5th》，我在练习中遇到了一些问题：

从 cin 读取单词序列并将值存储为向量。后 你已经阅读了所有单词，处理向量并将每个单词更改为 大写。打印转换后的元素，一行八个字。

我的代码是这样的：

#include <iostream>
#include <vector>
#include <string>
#include <cctype>

using std::vector;
using std::string;
using std::cin;
using std::cout;
using std::endl;

int main(){

    vector<string> words;
    string wordBuffer;
    vector<string> output(1);

    while (cin >> wordBuffer){
        words.push_back(wordBuffer);
    }

    for (string &word : words){
        for (char &letter : word){
            letter = toupper(letter);
        }
    }

    unsigned currentLine = 0;
    for (decltype(words.size())index = 0; index < words.size(); ++index){

        output[currentLine] += words[index] + " ";

        if ((index+1) % 8 == 0){
            ++currentLine;
            output.push_back("");
        }

    }

    for (string s : output){
        s[s.size() - 1] = 0; //removing the whitespace
        cout << s << endl;
    }

    system("pause");
    return 0;
}

现在，一切正常，但我在通过控制台输入单词时遇到问题。
如果我写

我正在写一个随机单词^Z

and press Enter nothing happens. I have to rewrite the ^Z after I have pressed the Enter, like here:

我正在写一个随机的单词
^Z

你能解释一下为什么吗？谢谢！

PS：我这么说是因为在我以前的程序中，在同一行中写入 ^Z 效果很好。就像这段代码一样：

#include <iostream>;


int main(){
    int currval = 0,val = 0;

        int count = 1;
        while (std::cin >> val){
            if (currval == val){
                ++count;
            }
            else {
                std::cout << "The number " << currval << " appears " << count << " times" << std::endl;
                currval = val;
                count = 1;
            }
        }
        std::cout << "The number " << currval << " appears " << count << " times" << std::endl;

    system("pause");

    return 0;
}

我不明白为什么:(

The ^Z has to be first in order for Windows to treat it as Ctrl+Z, otherwise it is just treated as meaningless characters.

如果您希望它像您所写的那样工作，我建议：

String wordBuffer("")
while (strcmp(wordBuffer[strlen(wordBuffer)-3], "^Z") != 0){
    words.push_back(wordBuffer);
    cin >> wordBuffer
}

EDIT: in your second example it works because when you read integers c++ knows to divide the given string of numbers in the space (or ENTER if the numbers are entered separately in every line) to read every number separately so if you'll enter:

123 2323 4545 43 ^Z

It will read 123, then 2323, ... and then ^Z and so it will be as though it got it in a separate line but when you read string, it cant do that because a string contain every symbol and so it separate the input in the ENTER pressed and that why the second one works