Unique Pointer in C++

#include <iostream>
#include <memory>
using namespace std;

class MyClass
{
public:
    void printMessage()
    {
        cout << "Hello World!" << endl;
    }
};
int main()
{
    unique_ptr<int> ptr(new int{500});
    cout << *ptr << endl;
    unique_ptr<int> uPtr = make_unique<int>(300);
    cout << *uPtr << endl;
    unique_ptr<MyClass> myClassPtr = make_unique<MyClass>();
    myClassPtr->printMessage();
    return 0;
}