无法退出for-loop，看似卡住了

Question

我最近选择了编码C ++，我正在学习使用Bjarne Stroustrup的入门书，我得到了这段代码：

// simple dictionary: list of sorted words
int main() {
    vector<string> words;
    for(string temp; cin>>temp;) // read whitespace-separated words
        words.push_back(temp); // put into vector
    cout << "Number of words: " << words.size() << '\n';

    sort(words); // sort the words

    for (int i = 0; i < words.size(); ++i)
        if (i == 0 || words[i–1] != words[i]) // is this a new word?
            cout << words[i] << '\n';
}

我复制了自己：

int main() {
    //variables.
    vector<string> dictionary;

    //prompts user to input words.
    cout << "input words in the dictionary:" << endl;
    while (dictionary.size() < 10) {
        for (string word; cin >> word;) {
            dictionary.push_back(word);
        }
    }
    //prints out number of words in the dictionary.
    cout << "number of words in the dictionary:" << dictionary.size() << endl;

    //sort the words and prints them out one by one, checking for repetitions.
    sort(dictionary.begin(), dictionary.end());
    for (int i = 0; i < dictionary.size(); ++i)
        if ((i == 0) || (dictionary[i-1] != dictionary[i]))
            cout << dictionary[i] << '\t';
    return 0;
}

但是这里有问题，我无法退出在字典中插入单词的初始循环（我添加的while循环是尝试修复它，但它似乎也不起作用）。

感谢您的时间 ：）。

Answer 1

内部for循环将一直运行，直到cin >> word为false，如果你继续添加有效字符串可能不是这种情况。此外，你不需要额外的包装for-loop。您可以执行以下操作，或在必要时添加break语句。

for (string word; cin >> word && dictionary.size() <10;) {
    dictionary.push_back(word);
 }