**Arrays: Operations**

**Traversal,
Insertion, Deletion **

*Pankaj Kumar Gupta*

*Head, BCA Department*

*Durga Prasad Baljeet Singh (PG) College,
Anoopshahr*

*District Bulandshahr (Uttar Pradesh)*

**Abstract: **

This Paper
describes full discussion about
operations of Array Data Structures like: Traversal, Insertion,
Deletion. Discussions about Algorithms and Procedures of same above defined
operations also made in this paper.

**Keywords:**

Array, Homogenous, Contiguous,
Linear, Primary, Lower Bound, Upper Bound, SDA, Insert, Delete, Traverse.

**Meaning of array:**

Computer Application we define Array as: *it is a Linear Data Structure. It is also
termed as a collection of homogenous data
elements. All the elements of an array share common name and stored on
contiguous locations. It is also categorized into derived data types.*

**Example: **

1.
A collection of
roll numbers of 50 students (int).

2.
A collection of
marks of 50 students in 6 subjects for a class (float).

3.
A collection of
names of 50 students (char).

**Categories of Arrays:**

Arrays are categorized into 3 categories
that are defined as follows:

1. Single
Dimensional Arrays.

2. Two Dimensional
Arrays.

3. Multidimensional
Arrays.

**Operations
of Array Data Structures:**

Various operations are performed on Array Data Structure,
that are as follows:

Here Discussion is made on Single Dimensional Array.

1.
Traversal

2.
Insertion

3.
Deletion

4.
Searching

5.
Sorting

6.
Merging

But
Traverse, Insert & Delete operations are discussed in this paper.

**Traversal:**** **

Traversal is a process of visiting each
and every node of a list in systematic manner. That means to go through each
and every item of the list at least once.

**Algorithm
TRAVERSEARRAY(A,N,LB,UB)**

/* Here
TRAVERSEARRAY is an algorithm which is used to traverse all the elements of
Array A with N elements. LB is Lower bound & UB is the Upper bound of
Array. */

Step-1 Start

Step-2 set K=LB.

Step-3 Repeat
steps 4 and 5 while K<=UB

Step-4 PROCESS
A[K].

Step-5 set
K=K+1.

Step-6 Exit.

**Insertion: **

Insertion is a
process of adding one or more items in the given list. If an array of elements
is given and an item is said to add at specific location. If array is already
full then insertion operation results *“Overflow”.
*To insert the item into array, all the elements from that location are
shifted to the right side of the Array.* *Specific
location may in:

1. Beginning of the Array

2. Middle anywhere

3. Last of the Array

*Here Lower bound is considered to be as 0.*

Array A is given as A[5]={1,2,3,4}

*Item to be inserted is 55 *

*Location is:*

**At
Beginning: ***New array will be like:*

**In
Middle anywhere (Loc=2 as index): ***New array will be like:*

**At
Last: ***New
array will be like:*

**Algorithm
INSERTARRAY(A,N,ITEM,LOC)**

/* Here
INSERTARRAY is an algorithm which is used to insert an ITEM on the Location LOC
in an Array A with N elements. Lower bound of A is considered to be 0. */

Step-1 Start

Step-2 set J=N.

Step-3 Repeat
steps 4 and 5 while K>=LOC

Step-4 set A[J]=A[J-1].

Step-5 set J=J-1.

Step-6 set
A[LOC]:=ITEM.

Step-7 set
N:=N+1.

Step-8 Exit.

**Deletion:**

Deletion is a
process of removing one or more items from given list. If an array of elements
is given and an item is said to remove from specific location. If array is
already empty then deletion operation results *“Underflow”. *To delete the item from array, all the elements from
that location are shifted from right to the left side of the Array in this way
the element that is to be deleted is overwritten by next element right to the
same location.* *Specific location may
in:

1. Beginning of the Array

2. Middle anywhere

3. Last of the Array

*Here Lower bound is considered to be as 0.*

Array A is given as A[5]={1,2,3,4,5}

*Item to be deleted is 1 on location 0 (i.e. Beginning) *

*New array will be like:*

*Item to be deleted is 3 on location 2 (i.e. Middle anywhere) *

*New array will be like:*

*Item to be deleted is 5 on location 4 (i.e. from Last) *

*New array will be like:*

Now from all
situations we decrease the size of array by 1 so that last element is removed
from Array.

**Algorithm
DELETEARRAY(A,N,ITEM,LOC)**

/*Here
DELETEARRAY is an algorithm which is used to delete an ITEM from the Location LOC in an Array A with N
elements. Lower bound of A is considered to be 0. */

Step-1 Start

Step-2 set
J:=LOC.

Step-3 set
ITEM:=A[LOC].

Step-4 Repeat
steps 4 and 5 while K<N

Step-5 set
A[J]:=A[J+1].

Step-6 set
J:=J+1.

Step-7 set
N:=N-1.

Step-8 Exit.

**Conclusion:**

An array can also be termed
as a collection of homogeneous values. Anybody can treat an array as a single
object by referring to it through a variable. Variable name is succeeded by
square brackets (that is
`[ ]`

symbols) But you can
also treat the components of the array as if they are themselves variables.
Traverse operation is made for going through all elements in an array. Insert operation is made for adding
one or more items in the array. Delete operation is made for removing one or
more items in the array.