I have to hold different type of datas in one array for my project. I've created a template class for generating objects.

template<class Queue>
class Template  {

public:
    Queue value;
    Template(Queue input) {
        value = input;
    }

};

But I can't hold them in one array without using abstract class. I've created a void pointer array for this. And I used it liked that;

void *array[21];
array[index] = new Template<int>(number);
array[index] = new Template<string>(text);

Is there any possible solution without abstract classes? I mean, can i hold this template objects in template class' array?

Create a hierarchy and take advantage of dynamic binding:

class Base  {
public:
  virtual ~Base() {};
  // ...
};

template<class Queue>
class Template : public Base {
    Queue value;
public:
    Template(Queue const &input) :value(input) {}
    // ...
};

And use it as:

Base *array[21];
array[index] = new Template<int>(number);
array[index + 1] = new Template<string>(text);

Furthermore, instead of using raw array and raw pointers use STL facilities like std::array smart pointers (e.g., std::shared_ptr<Base> or std::unique_ptr<Base>):

std::array<std::unique_ptr<Base>, 21> arr;
arr[index].reset(new Template<int>(number));
arr[index + 1].reset(new Template<string>(text));

Also prefer to initialize member variables to the constructor's initializer list than to its body.