Policy based smart pointer, C++ (gcc)

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//Title of this code

#include <iostream>
#include <stdexcept>
    
template<typename T>
struct NoCheckPolicy 
{
    NoCheckPolicy()
    {
    }
    
    static void Check(T *_p)
    {
        
    }
};
    
template<typename T>
struct FullCheckPolicy
{
    FullCheckPolicy()
    {
    }
    
    FullCheckPolicy(const NoCheckPolicy<T>&)
    {
    }
    
    static void Check(T *_p)
    {
        if (!_p)
        {
            throw std::runtime_error("Null pointer!");
        }
    }
};

template<typename T, 
    template<class>
    class CheckingPolicy = NoCheckPolicy>
class SmartPtr : public CheckingPolicy<T>
{
private:
    T *p_;
    
public:
    const T * getPtr() const
    {        
        return p_;
    }
    
    T * getPtr() 
    {        
        return p_;
    }
    
public:
    SmartPtr(T *p = NULL) : p_(p)
    {
    }
    
    template<
        template <class> class ChkPolicy>
    SmartPtr(const SmartPtr<T, ChkPolicy> &_ptr) : CheckingPolicy<T>(_ptr)
    {
        p_ = const_cast<T*>(_ptr.getPtr());
    }
    
    template<
        template <class> class ChkPolicy>
    SmartPtr & operator = (const SmartPtr<T, ChkPolicy> &_other)
    {
        SmartPtr temp(_other);
        
        p_ = const_cast<T*>(_other.getPtr());
        
        return *this;
    }
    
    const T * operator ->() const
    {
        CheckingPolicy<T>::Check(p_);
        
        return this->getPtr();
    }
    
    T * operator ->()
    {
        CheckingPolicy<T>::Check(p_);
        
        return this->getPtr();
    }
    
    const T & operator *() const
    {
        CheckingPolicy<T>::Check(p_);
     
        return this->getPtr();
    }
    
    T & operator *()
    {
        CheckingPolicy<T>::Check(p_);
        
        return *this->getPtr();
    }
};
    
template<typename T>
SmartPtr<T> make_smart(const T &val)
{
    SmartPtr<T> ptr = new T(val);
    
    return ptr;
}

int main()
{
    SmartPtr<int, FullCheckPolicy> ptr;
    SmartPtr<int, NoCheckPolicy> nocheckPtr;
    
    ptr = nocheckPtr;
    //nocheckPtr = ptr;
    
    //std::cout<<*nocheckPtr<<'\n';
    //std::cout<<*ptr<<'\n';
    
    ptr = make_smart(3);
    nocheckPtr = make_smart(5);
    //nocheckPtr = ptr;
    
    std::cout<<*nocheckPtr<<'\n';
    std::cout<<*ptr<<'\n';
    
    *ptr = 4;
    
    std::cout<<*ptr<<'\n';
}

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Compilation time: 0.3 sec, absolute running time: 0.14 sec, cpu time: 0 sec, memory peak: 3 Mb, absolute service time: 0.45 sec