array 2011
DESCRIPTION
Pointers and Array in C++TRANSCRIPT
2011 Topic: ARRAY by Atiqa, Rafia ; Rbiya, Rabia 1
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
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
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
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In some languages (e.g. COBOL) arrays are called “Tables”.
An individual value in an array is called an
“Element”
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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
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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]
We Explore The Following Things in this Section:
•Arrays Declaration
•Arrays Initialization
•With FOR Loop
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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….
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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 }
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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
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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…
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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
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• 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
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It has rows and columns…… just like a TABLE
Also known as MATRIX
EXAMPLE:
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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]
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 {}
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In GENERAL:
ARRAY_NAME[row][column]={row}{column}
[SUBSCRIPT]
Both parts of an index MUST be an integer
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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: }}
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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
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* 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
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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
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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!!!!
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1. C How to program, 4th edition by DEITEL
2. WWW.gavilian.edu/adnvantages/histroy/arrays.htm
3. WWW.agolist.net/data-strcutures/arrays
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