std :: cin输入带有空格？

#include <string>

std::string input;
std::cin >> input;

用户想要输入 Hello World。但是 cin 在两个单词之间的空格处失败。如何使 cin 进入整个？

The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?

我实际上是在使用结构体执行此操作，而 cin.getline 似乎不起作用。这是我的代码：

I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:

struct cd
{
    std::string CDTitle[50];
    std::string Artist[50];
    int number_of_songs[50];
};

std::cin.getline(library.number_of_songs[libNumber], 250);

这会产生错误。有任何想法吗？

This yields an error. Any ideas?