Page 18 - DCAP407_DATA_STRUCTURE

Unit 1: Introduction to Data Structures

3. Multidimensional Array: Multidimensional arrays can be defined as array of arrays.
Multidimensional arrays are not bounded to two indices or two dimensions. They can include as
many indices as required.
Linked List
A linked list is a data structure in which each data element contains a pointer or link to the next element
in the list. Through linked list, insertion and deletion of the data element is possible at all places of a
linear list. Also in linked list, it is not necessary to have the data elements stored in consecutive
locations. It allocates space for each data item in its own block of memory. Thus, a linked list is
considered as a chain of data elements or records called nodes. Each node in the list contains
information field and a pointer field. The information field contains the actual data and the pointer field
contains address of the subsequent nodes in the list.

Figure 1.3: A Linked List

Figure 1.3 represents a linked list with 4 nodes. Each node has two parts. The left part in the node
represents the information part which contains an entire record of data items and the right part
represents the pointer to the next node. The pointer of the last node contains a null pointer.
Stacks
A stack is an ordered list in which data items are inserted and deleted only from one end. It is also
known as Last-In First-Out list (LIFO) because the last element which enters the stack will be on top of
the stack and is the first one to come out.

Figure 1.4: A Stack

Figure 1.4 is a schematic diagram of a stack. Here, element FF is the top of the stack and element AA is
the bottom of the stack. Elements are added to the stack from the top. Since it follows LIFO pattern, EE

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