Doubt in linked list : insertion at head code

#1

I have written a question on line 28 and 29 ?

What is the difference in *arr and arr ?

And why we are using (*arr).next and not arr.next ?

#2

hello @yashsharma4304

arr is a pointer ( a datatype that stores address) .it has no other specialities.
we use dot operator over objects to call its member function or member variable right ?
so first we need to get the object from that pointer(arr).
and for that we are doing (*arr)
(*arr) : is representing an object and we can use dot operator on this object to get the content of its member variable.

#3

So arr is an object of node class. Node class has two data members

  1. data
  2. next

Now to access these data members of this class we will write :
(*arr).next or (*arr).data

Right?

Now, if we are writing *arr. Is that * used as a dereference operator or is it something else?

#4

yeah it is dereference operator only.

#5

Ok so if it is a dereferencing operator then it is giving us the value inside arr which is the address of a node to which it is pointing.

And here we are writing :

head = arr;

that means head will now point to arr and will store the address of arr.

But if I write :

head = *arr;

that means head is still pointing to the same node to which it was pointing ?

Indirectly we have not updated the value of head?

Because initially head was pointing to a node and our next node is now arr which stores the address of this previous node. So if I am writing :
head = *arr;
that means I am again copying the same address into head ?

Now, Is this concept right ?

#6

…

see arr is holding some address(say abcd)
then what dereference will do is it will give value present at address abcd.
and becuase at abcd we have stored object , it will give object.

#7

Then what is the name of that object ?

#8

no name bro, becuase we are using new operator.
what new operator does is , it return address of the newly created object .
we have only its address. and with the help of address we can access its member function and variable

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#9

Ok now it’s clear. Thank you

#10

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