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+1 vote
In a doubly linked list organization, insertion of a record in end involves modification of ____ for existing list.

one pointer

two pointer

multiple pointer

no pointer
asked in DS by Veteran (70k points) | 186 views
Last node changes 2 pointer, new node to be inserted changes 4 pointers.

Total = 6 pointers. Right?
i think at last node only 2 poinetrs are modified for exsting links.

Adding new node address to last node next pointer and new node previous=last node address.

only 2 pointers are modified.

Yeah if we're talking about only existing link. Only 2.

Answer is one

Answer is correct --> 1 

Here question ask modification in existence link only which will be the last link -> right pointer updated to point new last link, though we also modify new last link -> left to point to original last link [which is now second last].  

what it was previously?

last_link -> right =NULL;



new_last_link -> left= last_link -> right;

new_last_link ->right =NULL;


Small edit. @shreya

new_last_link -> left = last_link; [ not last_link -> right ]

last_link -> right = new_last_link;

1 Answer

+3 votes

I think  modification of only 2 pointers is need .

1. Make it the last link 

2. Make pointer to the previous node.


answered by (405 points)
ans: 1 pointer

Because in qus it is written that modification of existing list not the new node(not total modification if they ask total then ans will be 2 pointer).

In existing list we are modifying only last node next value.

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