The example of the creation of a dynamic array

Some useful functions to work with dynamic arrays are not realized in this program because it was written only to demonstrate the principle of creation such arrays.

The definition of the class:

template<class T>
class DynamicArray {
      long size;               //the size of the array
      long count;              //the count of elements in the array
      T* p;                    //the pionter to the beginning of the array

  public:
      //constructors
      DynamicArray(long s = 10): size(s), count(0) {
          p = new T[size];
      }
      DynamicArray(const DynamicArray& arr);    //copying costructor

      //destructor
      ~DynamicArray() {
          if(p) delete[] p;
      }

      //functions-members
      void add(T x);
      void remove();
      long length() const {return size;}
      void print() const;

      //operators
      DynamicArray& operator=(const DynamicArray& arr);  //assignment
      T operator [] (long i) const;                      //indexing
      DynamicArray& operator+(const DynamicArray& arr);
};

The implementation of functions and operators:

//copying costructor
template<class T>
DynamicArray<T>::DynamicArray(const DynamicArray& arr) {
    size = arr.size;
    count = arr.count;
    p = new T[size];
    for(int i = 0; i<count; ++i)
        p[i] = arr.p[i];
}

This function returns a value by reference to permit a programmer to create a chain of assignments:

template<class T>
DynamicArray<T>&        
DynamicArray<T>::operator=(const DynamicArray& arr)
      if(this != &arr) {       //to avoid assignments to itself
         size = arr.size;
         count = arr.count;
         if(p) delete[] p;
         p = new T[size];
         for(int i = 0; i<count; ++i) 
            p[i] = arr.p[i];

     }
     return *this;
}


template<class T>
T DynamicArray<T>::operator[](long i) const {
    if(i < size && i)
        return p[i-1];
    else
        return 0;
}


template<class T>
DynamicArray<T>& 
DynamicArray<T>::operator+(const DynamicArray& arr) {
    DynamicArray temp(*this);  //store values in a temporary array
    if(p) delete[] p;
    size += arr.size;
    count += arr.count;
    p = new T[size];
    for(int i = 0; i<temp.count; ++i)
         p[i] = temp.p[i];
    for(int i = 0; i<arr.count; ++i)
         p[temp.count + i] = arr.p[i];
    return *this;
}


template<class T>
void DynamicArray<T>::print() const {
    cout<<"The array contains:"<<endl;
    for(int i = 0; i<count; ++i)        
         cout<<p[i]<<' ';
    cout<<endl;
}


template<class T>
void DynamicArray<T>::add(T x) {
    if(count >= size) {
        DynamicArray temp(*this);
        if(p) delete[] p;
        size += 10;
        p = new T[size];
        for(int i = 0; i<temp.count; ++i)
            p[i] = temp.p[i];
    }
    p[count++] = x;           //add the element to the end of the array
}


template<class T>
void DynamicArray<T>::remove() {
   if(count)
       p[--count] = 0;    //delete the last element (if the array isn't
                          //empty)
}

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