ravi6771

 Profile Answers by ravi6771 

• Aug 12th, 2009

 

let suppose x is the node to be moved to top


x->next->prev=x->prev;
x->prev->next=x->prev->next->next;
x->next=head;
head->prev=x;
head=x;

f2003062

 Profile Answers by f2003062 

• Aug 19th, 2009

 

Lets say if the middle node of the doubly linked list is "middle" and the start node is "head".

then the code as follows.

middle->prev->next = middle->next;

middle->next->prev = middle->prev;

// Now make the middle as head.

middle->prev = NULL;

middle->next = head;

head->prev = middle;

head = middle;

kronos

 Profile Answers by kronos 

• Nov 16th, 2009

 

node *n1,*n2;
n1 = n2 = head;
while((n2->next) && (n2->next->next))
{
     n1 = n1->next;
     n2 = n2->next->next;
]

// n1 points to the middle now

n1->prev->next = n1->next;
n1->next->prev = n1->prev;
n1 ->prev = head ->prev; //NULL generally, non NULL value if circular list.
n1 ->next = head;
head = n1;