Как передалеть operator= класса?

#include <iostream>
using namespace std;
 
class CAT
{
    public:
        CAT();
        ~CAT();
        
        int GetAge() const { return *itsAge; }
        int GetWeight() const { return *itsWeight; }
        void SetAge(int age) { *itsAge = age; }
        CAT& operator=(const CAT&);
    
    private:
        int* itsAge;
        int* itsWeight;
};
 
CAT::~CAT()
{
    delete itsAge; itsAge=0;
    delete itsWeight; itsWeight=0;
}
 
CAT::CAT()
{
    itsAge = new int;
    itsWeight = new int;
    *itsAge = 5;
    *itsWeight=9;
}
 
CAT& CAT::operator=(const CAT& rhs)
{
    if(this == &rhs)
        return *this;
    
    *itsAge=rhs.GetAge();
    *itsWeight=rhs.GetWeight();
    return *this;
}
 
int main()
{
    CAT Frisky;
    cout << "Frisky's age: " << Frisky.GetAge() << endl;
    Frisky.SetAge(6);
    
    CAT whiskers = Frisky;
    Frisky.SetAge(0);
    cout << "whisker's age: " << whiskers.GetAge() << endl;
    
    return 0;
}

CAT whiskers = Frisky;

#include <iostream>
 
using namespace std;
 
class CAT
{
        public:
                CAT();
                CAT(const CAT& rhs);
                ~CAT();
                
                int GetAge() const { return *itsAge; }
                int GetWeight() const { return *itsWeight; }
                void SetAge(int age) { *itsAge = age; }
                CAT& operator=(const CAT&);
        
        private:
                int* itsAge;
                int* itsWeight;
};
 
CAT::~CAT()
{
        delete itsAge; itsAge=0;
        delete itsWeight; itsWeight=0;
}
 
CAT::CAT()
{
        itsAge = new int;
        itsWeight = new int;
        *itsAge = 5;
        *itsWeight=9;
}
 
CAT::CAT(const CAT& rhs)
{
       itsAge = new int;
       itsWeight = new int;
 
       *itsAge    = rhs.GetAge();
       *itsWeight = rhs.GetWeight();
}
 
CAT& CAT::operator=(const CAT& rhs)
{
        if(this == &rhs)
                return *this;
        
        *itsAge=rhs.GetAge();
        *itsWeight=rhs.GetWeight();
        return *this;
}
 
int main()
{
        CAT Frisky;
        cout << "Frisky's age: " << Frisky.GetAge() << endl;
        Frisky.SetAge(6);
        
        CAT whiskers = Frisky;
        Frisky.SetAge(0);
        cout << "whisker's age: " << whiskers.GetAge() << endl;
        
        return 0;
}

CAT::~CAT()
{
  delete itsAge;
  itsAge = 0;
 
  delete itsWeight;
  itsWeight = 0;
}