GATE CSE
First time here? Checkout the FAQ!
x
0 votes
104 views
To insert a node at the end of double linked list we need to modify two pointers right??But answer given is one pointer.
can someone clarify?
asked in Programming by Boss (8.2k points)  
edited by | 104 views

1 Answer

0 votes
Assume we have a pointer " LAST " which point to the last pointer

and we know LAST --> next = NULL

we create a new pointer called NEW and add it to end of LL

so we hv to modify following pointers :

LAST --> next = NEW

NEW  --> prev = LAST

NEW  --> next = NULL
answered by Loyal (2.9k points)  
ur approach is correct

but in made easy test series answer given is one only..

I think to insert at the end we are modifying only last->next = new which was null earlier

rest all ,we  are assigning not modifying.

new->next=null and new->prev=last both are assignment instead of modification.
if it like , how many links are modified in only given LL , i mean if we dont consider NEW node links
ya...because new node is not there in the list and we are just assiging the value to its data and link part then inserting it at the end so it is added not modified.

if something is already there and we are changing then we are are modifying the pointer.

So, only one pointer is modified which is last->link
I agree with @cse23

Related questions

Top Users Feb 2017
  1. Arjun

    4898 Points

  2. Bikram

    4102 Points

  3. Habibkhan

    3748 Points

  4. Aboveallplayer

    2986 Points

  5. sriv_shubham

    2288 Points

  6. Smriti012

    2222 Points

  7. Arnabi

    1946 Points

  8. Debashish Deka

    1920 Points

  9. mcjoshi

    1614 Points

  10. sh!va

    1462 Points

Monthly Topper: Rs. 500 gift card

20,793 questions
25,951 answers
59,557 comments
21,976 users