C++ Operator Overload array class, overloads assignment operator and copy constructor

 
 #include <iostream>
 using namespace std;
 class Array/*from   w  ww  .ja  v a 2 s  .  c  o  m*/
 {
    private:
    int* ptr;                 //pointer to "array" contents
    int size;                 //size of array
    public:
    Array() : ptr(0), size(0) //no-argument constructor
    { }
    Array(int s) : size(s)    //one-argument constructor
    { ptr = new int[s]; }
    Array(Array&);            //copy constructor
    ~Array()                  //destructor
    { delete[] ptr; }
    int& operator [] (int j)  //overloaded subscript op
    { return *(ptr+j); }
    Array& operator = (Array&);  //overloaded = operator
 };
 Array::Array(Array& a)          //copy constructor
 {
    size = a.size;               //new one is same size
    ptr = new int[size];         //get space for contents
    for(int j=0; j<size; j++)    //copy contents to new one
       *(ptr+j) = *(a.ptr+j);
 }
 Array& Array::operator = (Array& a)  //overloaded = operator
 {
       delete[] ptr;                //delete old contents (if any)
       size = a.size;               //make this object same size
       ptr = new int[a.size];       //get space for new contents
       for(int j=0; j<a.size; j++)  //copy contents to this object
          *(ptr+j) = *(a.ptr+j);
       return *this;                //return this object
 }
int main()
{
       const int ASIZE = 10;        //size of array
       Array arr1(ASIZE);           //make an array
       for(int j=0; j<ASIZE; j++)   //fill it with squares
          arr1[j] = j*j;
       Array arr2(arr1);            //use the copy constructor
       cout << "\narr2: ";
       for(j=0; j<ASIZE; j++)       //check that it worked
          cout << arr2[j] << "  ";
       Array arr3, arr4;            //make two empty Array objects
       arr4 = arr3 = arr1;          //use the assignment operator
       cout << "\narr3: ";
       for(j=0; j<ASIZE; j++)       //check that it worked on arr3
          cout << arr3[j] << "  ";
       cout << "\narr4: ";
       for(j=0; j<ASIZE; j++)       //check that it worked on arr4
          cout << arr4[j] << "  ";
       cout << endl;
       return 0;
}