1 Array Knowledge Understand the execute technique of array Skill Can write application program...

1

Array

KnowledgeUnderstand the execute technique of array

Skill Can write application program using one and two dimensional array

2

Why Array? Assume that you were asked to write a

program that accept 10 student marks,

calculating average mark, and then print

a number of students that get more than

average mark.

How to store all these marks?

#include <stdio.h>

void main() {int mark1, mark2, mark3, mark4, mark5, mark6, mark7, mark8, mark9, mark10;int bil=0, total_mark = 0;float Average_mark;

printf(“\nRead 10 test marks : \n”);scanf(“%d%d%d%d%d%d%d%d%d%d”, &mark1, &mark2,

&mark3, &mark4, &mark5, &mark6, &mark7, &mark8, &mark9, &mark10);

total_mark = mark1 + mark2 + mark3 + mark4 +mark5 + mark6 + mark7 + mark8 + mark9 + mark10;

Average_mark = (float) total_mark/10;

Read student marks

Solving Without Using Array

Solving Without Using Array#include <stdio.h>






Calculate the total mark

Solving Without Using Array

Calculate the average mark

#include <stdio.h>






if (mark1 > Average_mark) bil++;










printf(“\nAverage mark = %.2f”, purata);printf(“\n Number of students that get more than Average mark %d”, bil);

}

What would happen if there were 100 students?

Solving Without Using ArrayCalculate number of students which get more than Average mark

Solving Without Using Arrayif (mark1 > Average_mark)

bil++;if (mark2 > Average_mark)









bil++;

printf(“\nAverage mark = %.2f”, Average_mark);printf(“\n Number of students that get more than average mark = %d”, bil);

}

What would happen if there were 100 students?

Print the result

8

One-dimensional Array Instead of using 10 variables to represent 10

student marks,another technique is using one-dimensional array for storing a list of marks.

Array is a collection of memory location that is used for storing data from same type. Each memory location in array is referred by array’s name and location memory index.

9

One Dimensional Array67

mark

34

76

47

82

54

38

72

63

24

[0]

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

For printing each mark in array:

for (i=0; i < 10; i++)printf("%d ", mark[i])

Array name

10

One Dimensional Array67

mark

34

76

47

82

54

38

72

63

24

[0]

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

For printing each mark in array:

for (i=0; i < 10; i++)printf("%d ", mark[i])

Array Index

11

One-Dimensional Array Array declaration syntax

data_type name_of_array[integer_expression];

Example:

int mark[10];

In C programming, each index in array is start from 0. Thus, the last index number in one array of sized n is n-1.

12

Array Controlling One way for giving initial value to array’s

element is giving a list of initial value in array declaration.

13

Array Controlling Example:

int month[12] = { 31, 28, 31, 30, 31,30, 31, 31, 30, 31, 30, 31 };

month

31

31

28

30

3031

31

30

31

31

[0]

[1][2][3][4]

[5][6]

[7][8][9]

3031

[10]

[11]

14

Array Controlling If the list of initial value is

less than array size, the rest element will be given 0 value

int month[12] = { 31, 28, 31, 30, 31 }

month

31

31

28

30

031

0

0

0

0

[0]

[1][2][3][4]

[5][6]

[7][8][9]

00

[10]

[11]

15

Array Controlling Array size can be ignore

in declaration if it is given by initial value list. Array size will be set based on a number of data in their list.

int month[ ] = { 31, 28, 31, 30, 31 }

month

31

31

28

3031

[0]

[1][2][3][4]

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Array Assignment Value assignment to array’s element is

same as value assign to variable.

Assignment to array can be done element by element.

17

Array Assignment Example:

tinggi

???

???

???

??????

[0]

[1][2]

[3][4]

float tinggi[5];tinggi[0] = 31.34;tinggi[1] = 28.11;tinggi[2] = 31.25;tinggi[3] = 30.94;tinggi[4] = 31.68;

18

Array Assignment

tinggi

31.34

???

???

??????

[0]

[1][2]

[3][4]


Example:

19

Array Assignment

tinggi

31.34

???

28.11

??????

[0]

[1][2]

[3][4]


Example:

20

Array Assignment

tinggi

31.34

31.25

28.11

??????

[0]

[1][2]

[3][4]


Example:

21

Array Assignment

tinggi

31.34

31.25

28.11

30.94???

[0]

[1][2]

[3][4]


Example:

22

Array Assignment

tinggi

31.34

31.25

28.11

30.9431.68

[0]

[1][2]

[3][4]


Example:

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Array Assignment In certain situation, array assignment

can be write using looping.

number

???

???

???

??????

[0][1][2]

[3][4]

i???

int number[5], i;for (i=0; i < 5; i++)

number[i] = 0;

24


can be write using looping

number

???

???

???

??????

[0][1][2]

[3][4]

i0


number[i] = 0;

25



number

???

???

???

??????

[0][1][2]

[3][4]

i0


number[i] = 0;

0<5TRUE

26



number

0

???

???

??????

[0][1][2]

[3][4]

i0


number[i] = 0;

27



number

0

???

???

??????

[0][1][2]

[3][4]

i1


number[i] = 0;

28



number

0

???

???

??????

[0][1][2]

[3][4]

i1


number[i] = 0;

1<5TRUE

29



number

0

???

0

??????

[0][1][2]

[3][4]

i1


number[i] = 0;

30



number

0

???

0

??????

[0][1][2]

[3][4]

i2


number[i] = 0;

31



number

0

???

0

??????

[0][1][2]

[3][4]

i2


number[i] = 0;

2<5TRUE

32



number

0

0

0

??????

[0][1][2]

[3][4]

i2


number[i] = 0;

33



number

0

0

0

??????

[0][1][2]

[3][4]

i3


number[i] = 0;

34



number

0

0

0

??????

[0][1][2]

[3][4]

i3


number[i] = 0;

3<5TRUE

35



number

0

0

0

0???

[0][1][2]

[3][4]

i3


number[i] = 0;

36



number

0

0

0

0???

[0][1][2]

[3][4]

i4


number[i] = 0;

37



number

0

0

0

0???

[0][1][2]

[3][4]

i4


number[i] = 0;

4<5TRUE

38



number

0

0

0

00

[0][1][2]

[3][4]

i4


number[i] = 0;

39



number

0

0

0

00

[0][1][2]

[3][4]

i5


number[i] = 0;

40



number

0

0

0

00

[0][1][2]

[3][4]


number[i] = 0;

i5

5<5FALSE

41



number

0

0

0

00

[0][1][2]

[3][4]


number[i] = 0;

i5

42

Example of Using Array

Program to process 3 student mark

Read studentsmark

Calculate number of

mark greater than Average

mark

Calculate Total mark

All Studentsmark

CalculateAverage mark

All Studentsmark

Totalmark

Total mark

Averagemark

All studentsMark,Average mark

number

Print the result

Average mark, number

Example of Using Array#include <stdio.h>void main() {

int mark[3], i, bil, total_mark;float Average_mark;

for (i = 0; i < 3, i++) {printf(“Enter mark %d : “, i);scanf(“%d”, &mark[i]);

}total_mark= 0;for (i = 0; i < 3; i++)

total_mark += mark[i];Average_mark = (float) total_mark / 3;bil = 0;for (i = 0; i < 3; i++ )

if (mark[i] > Average_mark)bil++;

printf(“\nAverage mark= %.2f”, Average_mark);printf(“\nNumber of students that get more than average mark = %d\n”, bil);

}

Read student marks








}

Calculate total mark








}

Calculate the average mark

#include <stdio.h>void main() {







}

Example of Using Array

Calculate the number of student that get more than average mark








}

Print the result







printf(“\nAverage mark= %.2f”, Average_mark);printf(“\nNumber of mark that are greater than average = %d\n”, bil);

}

???

???

???

???

???

???

???

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}

Example of Using Array0

???

???

???

???

???

???

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

???

???

???

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

0<3TRUE








}


???

???

???

70

???

???

Enter mark 0: 70_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

70

???

???

Enter mark 0: 70

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

1<3TRUE








}


???

???

???

70

30

???

Enter mark 0: 70Enter mark 1: 30

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

70

30

???

Enter mark 0: 70Enter mark 1: 30 _

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

70

30

???

Enter mark 0: 70Enter mark 1: 30__

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

2<3TRUE








}


???

???

???

70

30

80

Enter mark 0: 70Enter mark 1: 30Enter mark 2: 80_

_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

70

30

80

Enter mark 0: 70Enter mark 1: 30Enter mark 2: 80__

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

???

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

3<3FALSE








}


???

0

???

70

30

80


i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

0

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

0

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

0<3TRUE








}


???

70

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

70

???

70

30

80


i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

70

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

1<3TRUE








}


???

100

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

100

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

2<3TRUE








}


???

180

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


???

180

???

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

3<3FALSE








}


???

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark







printf(“\nAverage mark= %.2f”, Average_mark); printf(“\nNumber of students that get more than average mark = %d\n”,

bil);}


0

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


0

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


0

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark0<3TRUE








}


0

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark









1

180

60.00

70

30

80

Enter mark 0: 70Enter mark 1: 30Enter mark 2: 80_ i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


1

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


1

180

60.00

70

30

80


bil

total_mark

Average_mark

[0]

[1]

[2]

mark1<3TRUE








}


1

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


1

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark2<3TRUE








}


1

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


2

180

60.00

70

30

80


_

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark








}


2

180

60.00

70

30

80


bil

total_mark

Average_mark

[0]

[1]

[2]

mark

86








}


2

180

60.00

70

30

80


bil

total_mark

Average_mark

[0]

[1]

[2]

mark3<3FALSE

87








}


2

180

60.00

70

30

80

Enter mark 0: 70Enter mark 1: 30Enter mark 2: 80

Average mark= 60.00Number of students that get more than average mark = 2 _

i

bil

total_mark

Average_mark

[0]

[1]

[2]

mark

1 Array Knowledge Understand the execute technique of array Skill Can write application program...

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