class Teacher { public: int id; int* studentIds{nullptr}; int count;
public: Teacher(int id, int count) { this->id = id; this->count = count; this->studentIds = new int[count]; }
Teacher(Teacher&& other) { this->id = other.id; this->count = other.count; this->studentIds = other.studentIds; other.studentIds = nullptr; }
// copy构造函数尽量不给出实现，如果不给出，因为提供了移动copy，所以这个函数是不允许调用的 // Teacher(Teacher& other) { // this->id = id; // this->count = count; // this->studentIds = other.studentIds; //这里简单这么实现，通常需要深copy，否则可能出现内存被重复释放的问题 // }
Teacher& operator=(Teacher&& other) { if (this->studentIds) { delete this->studentIds; } }
// 这个函数尽量不提供，如果需要提供，则需要深copy，因为出现了移动赋值，如果不提供改函数，该函数是不允许使用的 // Teacher& operator=(Teacher& other) {
// } ~Teacher() { if (this->studentIds) { delete this->studentIds; this->studentIds = nullptr; } } };
Teacher GetTeacher() { // 借助了移动copy构造函数的能力，相当于返回了局部变量 Teacher t(1, 4); for (int i = 0; i < t.count; i++) { t.studentIds[i] = i; } return t; }
int main(int argc, char const* argv[]) { Teacher p = GetTeacher();
cout << p.id << " " << p.count << endl; for (int i = 0; i < p.count; i++) { cout << p.studentIds[i] << " "; } cout << endl; return 0; }