Basic Fundamental Of Array

1. ARRAY
Tejas Patel
Harekrushna Patel
Page 1

2. Content…
•
•
•
•
What are arrays?
Types of arrays
Single dimensional array
Multi dimensional array
Page 2

3. What are Arrays?
• Array is a data structure, which provides the facility to
store a collection of data of same type under single
variable name.
• It is a group of consecutive memory locations having same
name and type.
Page 3

4. Types
• One dimensional
• Multi dimensional
Page 4

5. Single Dimensional Array
• Element specified by single subscript
• Array declaration is made by specifying the data type, it’s
name and the number of space (size) so that the computer
may reserve the appropriate amount of memory.
Syntax
type array_name [ size ]
Base
type of
array
Name of No. of elements that can be
array
stored: Can be a integer
value without the sign
Page 5

6. Single dimensional Array Working
When user inputting data in array
i=0
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
a[0]
a[1]
a[2]
a[3]
a[4]
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7. Single dimensional Array Working
When user inputting data in array
i=0
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
a[0]
a[1]
a[2]
a[3]
a[4]
Page 7

8. Single dimensional Array Working
When user inputting data in array
i=0
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
a[0]
a[1]
a[2]
a[3]
a[4]
Page 8

9. Single dimensional Array Working
When user inputting data in array
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
i=1
5
a[0]
a[1]
a[2]
a[3]
a[4]
Page 9

10. Single dimensional Array Working
When user inputting data in array
i=1
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
a[0]
a[1]
a[2]
a[3]
a[4]
Page 10

11. Single dimensional Array Working
When user inputting data in array
i=1
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
a[0]
a[1]
a[2]
a[3]
a[4]
Page 11

12. Single dimensional Array Working
When user inputting data in array
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
i=2
5
10
a[0]
a[1]
a[2]
a[3]
a[4]
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13. Single dimensional Array Working
When user inputting data in array
i=2
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
a[0]
a[1]
a[2]
a[3]
a[4]
Page 13

14. Single dimensional Array Working
When user inputting data in array
i=2
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
a[3]
a[4]
Page 14

15. Single dimensional Array Working
When user inputting data in array
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
i=3
5
10
15
a[0]
a[1]
a[2]
a[3]
a[4]
Page 15

16. Single dimensional Array Working
When user inputting data in array
i=3
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
a[3]
a[4]
Page 16

17. Single dimensional Array Working
When user inputting data in array
i=3
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
a[3]
a[4]
Page 17

18. Single dimensional Array Working
When user inputting data in array
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
i=4
5
10
15
a[0]
a[1]
a[2]
20
a[3]
a[4]
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19. Single dimensional Array Working
When user inputting data in array
i=4
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
a[3]
a[4]
Page 19

20. Single dimensional Array Working
When user inputting data in array
i=4
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
25
a[3]
a[4]
Page 20

21. Single dimensional Array Working
When user inputting data in array
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
i=5
5
10
15
a[0]
a[1]
a[2]
20
25
a[3]
a[4]
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22. Single dimensional Array Working
When user inputting data in array
i=5
i=5
for(i=0;i<5;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
25
a[3]
a[4]
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23. Single dimensional Array Working
When user inputting data in array
i=5
i=5
for(i=0; i<5 ;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
25
a[3]
a[4]
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24. Single dimensional Array Working
When user inputting data in array
i=5
i=5
Here, i=5 & condition is i<5 so
condition not satisfied
for(i=0; i<5 ;i++)
{
scanf(“%d”,&a[i]);
}
5
10
15
a[0]
a[1]
a[2]
20
25
a[3]
a[4]
Page 24

25. Two Dimensional Array
• A two dimensional array is a collection of elements placed in
rows and columns.
• The syntax used to declare two dimensional array includes two
subscripts, of which one specifies the number of rows and the
other specifies the number of columns.
• These two subscripts are used to reference an element in an
array.
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26. Syntax
<data type> <array name> [row size]
[column size];
<data type> <array name> [row size] [column size]={values};
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27. Example
int num[3][2]={4,3,5,6,8,9};
or
int num[3][2]={{4,3},{5,6},{8,9}};
values
column size
row size
array name
data type
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28. Representation of the 2-D Array
Rows
columns
0th column
1st column
0th row
1st row
2nd row
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29. Multi dimensional Arrays
• An array haves 2 or more subscripts, that type of array is called
multi dimensional array.
• The 3 –D array is called as multidimensional array this can be
thought of as an array of two dimensional arrays.
• Each element of a 3-D array is accessed using subscripts, one
for each dimension.
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30. Multiple Dimensional Array
• Tables with rows and columns (m by n array)
• Like matrices: specify row, then column
Column 0
Column 1
Column 2
Column 3
Row 0
a[ 0 ][ 0 ]
a[ 0 ][ 1 ]
a[ 0 ][ 2 ]
a[ 0 ][ 3 ]
Row 1
a[ 1 ][ 0 ]
a[ 1 ][ 1 ]
a[ 1 ][ 2 ]
a[ 1 ][ 3 ]
a[ 2 ][ 0 ]
a[ 2 ][ 1 ]
a[ 2 ][ 2 ]
a[ 2 ][ 3 ]
Row 2
Column subscript
Array name
Row subscript
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31. Initialization
• int b[2][2] = {{1,2},{3,4}};
• Initializers grouped by row in braces
• If not enough, unspecified elements set to zero
int b[2][2] = {{1},{3,4}};
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32. Important
• The most important thing to remember about array
allocation is that the elements of the array are indexed
starting at 0, not 1. If the number of cells in an array is
N, then the indexes run from 0 to N-1.
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