Object array initialization without default constructor

Question

#include 
class Car
{
private:
  Car(){};
  int _no;
public:
  Car(int no)
  {
    _no=no;
  }
  void printNo()
  {
    std::cout<<_no<

        

Answer 1

You can use in-place operator new. This would be a bit horrible, and I'd recommend keeping in a factory.

Car* createCars(unsigned number)
{
    if (number == 0 )
        return 0;
    Car* cars = reinterpret_cast(new char[sizeof(Car)* number]);
    for(unsigned carId = 0;
        carId != number;
        ++carId)
    {
        new(cars+carId) Car(carId);
    }
    return cars;
}

And define a corresponding destroy so as to match the new used in this.