Arrays

1. 2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 1

2.  Introduction to the ARRAY
 Classification
 Array Declaration
 Array Initialization
 Array with FOR Loop
 Upper and lower limit of Array
 Advantages
 Disadvantages
 Conclusion
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 2

3.  An Array is a group of memory location s
having same data type
 Data type specify the type of data it stores
 A group of CONTINOUS memory locations
Example: Int A[0][1][2][3][4]
 Store JUST single variable
 C++ store list values in it
 Arrange in Rows/ Columns
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 3

4. To refer a particular location its Name and
its “SUBSCRIPT “is specifies
WHAT IS A „SUBSCRIPT‟?
The number contained within Square bracket
It MUST be an integer or expression
If its an integer expression then it is
evaluated to describe the subscript
EXAMPLE:
c[a+b] +=2; if a=5, and b=6
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 4

5. In some languages (e.g. COBOL) arrays are
called “Tables”.
An individual value in an array is called an
“Element”
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 5

6. There are divided into following types;
1. One Dimensional Arrays:
A[0][1][2][3][4][5][6]………………[n]
2. Two Dimensional Arrays:
3. Multi Dimensional Arrays:
3D, 4D etc
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 6
A[0][0] A[0][1] A[0][2] A[0][3] A[0][4]
A[1][0] A[1][1] A[1][2] A[1][3] A[1][4]
A[2][0] A[2][1] A[2][2] A[2][3] A[2][4]

7. We Explore The Following Things in this Section:
•Arrays Declaration
•Arrays Initialization
•With FOR Loop
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 7

8. As just in few steps…
Lets have an example of OVERS in a cricket
match, its 6 per over
We declared it something like that…
Int balls[5]
Subscript/index
Array_name
OR….
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 8

9. Its still the same!!!
Int balls= {1,2,3,4,5,6}
More Examplex:
Char city= {L,A,H,O,R,E}
FLOAT NUM={1.2, 1.3, 1.4 ,1.5 }
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 9

10. It can be intialized as they declared
Do not need to declared the subscript if initial
values are defined
What's the initial values we are talking about..
Int k[]= {12,13,14,15}
WE HAVENT SEPCIFY THE INDEX-ANOTHER
NAME AND STIL IT WORKS
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 10

11. Because array automatically generate the
space for it
JUST FOR UNDERSTANDING!!!
Int k [5]= {12,13,14,15}
With index it something look like this…..
C++ does not flag out any error if index go
out of the bound…
HOW?????
Char k[7]={A,R,R,A,Y}
Even the memory remains empty still it does
not cerate any error…
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 11

12. Almost always needed to steep through the ARRAY
The loop is used is “FOR-LOOP”
Can not do manipulation easily then
BUT WHY?????
 Loops are use to REPEATATION
so as in the case of array we MUXT declared the
index of ≥0 ; for
 C++ to pick up the required index it uses the loop.
But just not used in some fewer cases
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 12

13. 2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 13

14. • We „r going to explore the following contents in
this:
1. Introduction to 2D-Array
2. 2D Array with nested FOR loop
3. Upper and lower limit of array
4. Advantages
5. Disadvantages
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 14

15. It has rows and columns…… just like a
TABLE
Also known as MATRIX
EXAMPLE:
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 15
A[0][0] A[0][1] A[0][2] A[0][3] A[0][4]
A[1][0] A[1][1] A[1][2] A[1][3] A[1][4]
A[2][0] A[2][1] A[2][2] A[2][3] A[2][4]

16. HOW TO DECLARE 2D-ARRAY??? This way
Int temps[2][2]
Row * column = 2*2: holding 4 integers
NOW HOW to INITIALIZE IT??????
JUST simple!!!
Int temps[2][2]={{12,14} , {21,41}}:
Value of each is held in {}
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 16

17. In GENERAL:
ARRAY_NAME[row][column]={row}{column}
[SUBSCRIPT]
Both parts of an index MUST be an integer
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 17

18. Nested FOR loops to step through 2D-Array
USUALL FORMAT:
FOR EACH ROW, FOR EACH COLUMN
Do something to array[row][column]
EXAMPLE:
Int team[2][3];
For(int row=0;orw<2;;row++){
For(int row=0;orw<2;;row++){
Team[row][column]=8: }}
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 18

19. 2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 19

20. Mid versions of BASIC allowed any starting
and ending value. So we could have arrays like
the following:
EXAMPLE:
int years (1998 to 2008)
int tide. level(-5 to +5)
 Many “modern” languages do not allow this
freedom with declaring arrays
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 20

21. * simple and easy to create
Any element of an array can be accessed time
by its index
Random access
Constant size
arrays with arbitrary size (dynamically
allocated array)
array will always hold similar kind of information
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 21

22. We cant change the size of array during run
time
Constant size WITH Constant data-type
Array data structure is not completely
dynamic.
Insertion and deletion of an element in the
array requires to shift the locations
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 22

23. The Prospective of what we have presented
now is to JUST enhance the ability of
ourselves;
Its up to US how we cater down al this in
our practical LIFE…
We have to crave what is perfect from
INSIDE!!!!
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 23

24. 1. C How to program, 4th edition by DEITEL
2. WWW.gavilian.edu/adnvantages/histroy/a
rrays.htm
3. WWW.agolist.net/data-strcutures/arrays
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