I believe it's simply a list of objects, with each object pointing to the next object. There is a value which keeps track of the list location (the head). Also the last object points to null.
head ----- data|pointer -----> data|pointer -----> data|pointer -----> data|NULL
This is a very basic form of such a list, and it's pretty inefficient, especially when it comes to adding values to the end of the list. A way to improve that would be to add a 'tail' variable so the last value can be easily found.
You copy a singly linked list into a doubly linked list by iterating over the singly linked list and, for each element, calling the doubly linked list insert function.
Traversing a doubly linked list is generally faster than traversing a singly linked list, but the speedup depends on how you do the traversal:Traversing from first to last node: No difference.Random access: Doubly linked list is faster, the difference is a fixed factor. (Like twice as fast. Which makes it still very slow for random access compared to arrays.)Reverse order: Doubly linked list is just as fast traversing "backwards" as "forwards", while a singly linked list traversing in reverse order needs to traverse the entire list once for every element in the list - it is a LOT slower. (Time complexity O(n) for doubly linked list, O(n*n) for singly linked, if you are familiar with the notation.)If you are talking about the computer science "big O notation", doubly linked and singly liked lists are the same. This is because the Big O notation ignores fixed factors and only looks at how time increases with the length of the list, and in this respect the two are the same. (Except for the special case of traversing the list in reverse order. Even here a singly linked list could do it in O(n) time - same as a doubly linked list - by reversing the list (O(n)) before traversing it (O(n)) for a total time of 2*O(n), which by the rules of Big O is the same as O(n).)
3 pointers...
O(m*n).
The top of a stack implemented as a linked list is the head of the list. All insertions and extractions occur at the head thus a forward list (singly-linked list) is sufficient to implement a stack.
yes
You copy a singly linked list into a doubly linked list by iterating over the singly linked list and, for each element, calling the doubly linked list insert function.
This is a searching question.
singly linked list stores only the address of next node while doubly linked list stores the address of previous node and next node and hence it is called doubly linked list. In singly linked list only forward traversing is possible while in doubly linked list forward and backward traversal is possible.
It is easier to insert into a singly linked list.
Traversing a doubly linked list is generally faster than traversing a singly linked list, but the speedup depends on how you do the traversal:Traversing from first to last node: No difference.Random access: Doubly linked list is faster, the difference is a fixed factor. (Like twice as fast. Which makes it still very slow for random access compared to arrays.)Reverse order: Doubly linked list is just as fast traversing "backwards" as "forwards", while a singly linked list traversing in reverse order needs to traverse the entire list once for every element in the list - it is a LOT slower. (Time complexity O(n) for doubly linked list, O(n*n) for singly linked, if you are familiar with the notation.)If you are talking about the computer science "big O notation", doubly linked and singly liked lists are the same. This is because the Big O notation ignores fixed factors and only looks at how time increases with the length of the list, and in this respect the two are the same. (Except for the special case of traversing the list in reverse order. Even here a singly linked list could do it in O(n) time - same as a doubly linked list - by reversing the list (O(n)) before traversing it (O(n)) for a total time of 2*O(n), which by the rules of Big O is the same as O(n).)
A singly linked list is a linked list which only provides links in "one direction". Using a metaphor, a singly linked list is a one way street, while a doubly linked list is a two way street. Once you move forward in a singly linked list, there is no way to go backwards unless you kept your reference/pointer from before. A singly linked list would look like this: start ----> node1---->node2---->node3 ----> NULL You will see that node2 only has a link forward to node3 - it does not have a link backwards to node1, even though node1 has a link forwards to node2. To prevent us from permanently losing access to portions of the linked list, we generally keep a reference/pointer to "start". A doubly linked list would have twice the number of pointers/references as a singly linked list - making it very inefficient to store small datatypes. On the other hand, it would be possible to move both forwards and backwards with a doubly linked list because you have links pointing both forwards and backwards.
3 pointers...
To implement a doubly linked list using a singly linked list, you can create two nodes in each element of the singly linked list - one for the next element and another for the previous element. This way, each node will have access to both its previous and next nodes, effectively creating a doubly linked list structure using a singly linked list implementation.
write a c program to circular queue
O(m*n).
The top of a stack implemented as a linked list is the head of the list. All insertions and extractions occur at the head thus a forward list (singly-linked list) is sufficient to implement a stack.