尝试将cin转换为字符串时出现分段错误？

Question

Hi need help with this segmentation fault don't know why i get it

Movie *newMovie = (Movie*) malloc(sizeof(Movie));
cout << "\nEnter the next movie title:   ";
cin >> newMovie->title;

class Movie {
  public:
    Movie();
    std::string title;
    int year;
    GenreType genre;
};

I checked dgb and segmentation fault comes at the cin line any suggestions? btw title is an instance of Movie type and is std::string

Answer 1

Don't use malloc in C++ unless you really know you need it (hint: you don't).

malloc allocates memory, but it doesn't call any constructors - it just gives you a chunk of bytes to treat as you see fit. Pretending there's an object in these bytes when none was constructed doesn't work.

So just do this:

Movie *newMovie = new Movie();
cout << "\nEnter the next movie title:   ";
cin >> newMovie->title;

And do you need dynamic allocation in the first place? Why not just:

Movie newMovie;
cout << "\nEnter the next movie title:   ";
cin >> newMovie.title;

Answer 2

The simple amd safe way to do this would be not to use dynamic allocation:

Movie newMovie;
cout << "\nEnter the next movie title:   ";
cin >> newMovie.title;

Answer 3

Movie newMovie;
cout << "\nEnter the next movie title ";
cin >> newMovie.title;

will do the trick