A linked list is a data structure which consists of data record in a sequence such that each data record have a field of data as well as link reference to its connected node. It do not provide the random access to any of its member data as it is form of a indexing and the connected node is pre-defined.
In the singly link list each node have two fields one for data and other is for link reference of the next node. The node have null only to the last node of the link field. This can be seen in the following picuture.
Fig: Singly Link List
In the doubly link list each node have three field two fields for link which is the reference to next and previous and one for data record. The node have null only to the first node of previous and last node at the next. This can be seen in the following picture.
Fig: Doubly Link List
If talking about singly circular link list each node have two fields one for data record and other for link reference to the next node. The last node has link reference to the first node. There in no null present in the link of any node.
Fig: Singly circular link list
In the next page you will see various example with this context.
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