ARRAY
Tejas Patel
Harekrushna Patel
Page 1
Content…
•
•
•
•

What are arrays?
Types of arrays
Single dimensional array
Multi dimensional array

Page 2
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
Types
• One dimensional
• Multi dimensional

Page 4
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
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 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]
Page 7
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
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
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
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
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]
Page 12
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
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
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
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
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
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]
Page 18
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
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
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]
Page 21
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]
Page 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]
Page 23
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
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.

Page 25
Syntax
<data type> <array name> [row size]

[column size];

<data type> <array name> [row size] [column size]={values};

Page 26
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

Page 27
Representation of the 2-D Array
Rows

columns

0th column

1st column

0th row
1st row
2nd row

Page 28
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.

Page 29
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

Page 30
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}};

Page 31
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.

Page 32
Array

Array

  • 1.
  • 2.
    Content… • • • • What are arrays? Typesof 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 ArrayWorking 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 6
  • 7.
    Single dimensional ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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] Page 12
  • 13.
    Single dimensional ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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 ArrayWorking 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] Page 18
  • 19.
    Single dimensional ArrayWorking 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 ArrayWorking 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 ArrayWorking 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] Page 21
  • 22.
    Single dimensional ArrayWorking 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] Page 22
  • 23.
    Single dimensional ArrayWorking 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] Page 23
  • 24.
    Single dimensional ArrayWorking 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. Page 25
  • 26.
    Syntax <data type> <arrayname> [row size] [column size]; <data type> <array name> [row size] [column size]={values}; Page 26
  • 27.
  • 28.
    Representation of the2-D Array Rows columns 0th column 1st column 0th row 1st row 2nd row Page 28
  • 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. Page 29
  • 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 Page 30
  • 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}}; Page 31
  • 32.
    Important • The mostimportant 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. Page 32