Answer Posted / akhilesh kumar jaiswal

A smart pointer is an object that acts, looks and feels like a normal pointer but offers more functionality. In C++, smart pointers are implemented as template classes that encapsulate a pointer and override standard pointer operators. They have a number of advantages over regular pointers. They are guaranteed to be initialized as either null pointers or pointers to a heap object. Indirection through a null pointer is checked. No delete is ever necessary. Objects are automatically freed when the last pointer to them has gone away. One significant problem with these smart pointers is that unlike regular pointers, they don't respect inheritance. Smart pointers are unattractive for polymorphic code. Given below is an example for the implementation of smart pointers.
Example:
template <class X>
class smart_pointer
{
public:
smart_pointer(); // makes a null pointer
smart_pointer(const X& x) // makes pointer to copy of x

X& operator *( );
const X& operator*( ) const;
X* operator->() const;

smart_pointer(const smart_pointer <X> &);
const smart_pointer <X> & operator =(const smart_pointer<X>&);
~smart_pointer();
private:
//...
};
This class implement a smart pointer to an object of type X. The object itself is located on the heap. Here is how to use it:
smart_pointer <employee> p= employee("Harris",1333);
Like other overloaded operators, p will behave like a regular pointer,
cout<<*p;
p->raise_salary(0.5);

What is the use of "new" operator?

1092

---

Define linked lists with the help of an example.

996

---

Will the following program execute?

1001

---

Is turbo c++ free?

1025

---

What is the difference between while and do while loop?

1101

---

If a function doesn’t return a value, how do you declare the function?

1019

---

What does asterisk mean in c++?

1079

---

Write a program which is required to process the time of a clock in hours and minutes, entered from the keyboard. With this program, there are two requirements for any data entered by a user: 1. The data must be of the correct type (in this case, two ints). 2. The data must be in the correct range: this means that, for the minutes, negative numbers and any number above 59 must be rejected; for the hours, negative numbers and any number above 23 must be rejected. Output error message for invalid data input. Output the time one and a half hour after the time input. i.e. Hour: 22 Min: 32 One and a half hour after 22:32 is 00:02

1925

---

Is there structure in c++?

984

---

Explain the scope of resolution operator.

1062

---

What is the output of the following program? Why?

1106

---

What is the syntax for a for loop?

1093

---

Explain the difference between class and struct in c++?

1007

---

What is the difference between C and CPP?

1122

---

Why is main an int?

944

---