1. Edited from Powerpoint Slides provided by Thomson Learning
C++ Programming: From Problem Analysis to Program Design, Fourth Edition
Topic 4 : Records
Edited from Powerpoint Slides
provided by Thomson Learning

2. Objectives In this chapter, you will: Learn about records (structs)
Examine various operations on a struct
Explore ways to manipulate data using a struct
Learn about the relationship between a struct and functions
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

3. Records (structs)
struct: collection of a fixed number of components (members), accessed by name
Members may be of different types
Syntax:
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

4. Programming Example
struct studentType { char firstName[20]; char lastName[20]; char courseGrade; int testScore; int programmingScore; double GPA; }; void main( ) studentType newStudent; studentType student; newStudent.GPA = 0.0; strcpy(newStudent.firstName,"John"); strcpy(newStudent.lastName,"Brown"); }
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

5. Records (structs) (continued)
A struct is a definition, not a declaration
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

6. Records (structs) (continued)
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

7. Accessing struct Members
The syntax for accessing a struct member is:
The dot (.) is an operator, called the member access operator
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

8. Accessing struct Members (continued)
To initialize the members of newStudent:
newStudent.GPA = 0.0;
strcpy(newStudent.firstName,"John“);
strcpy(newStudent.lastName,"Brown“);
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

9. Accessing struct Members (continued)
More examples:
cin.getline(newStudent.firstName,20);
cin >> newStudent.testScore >> newStudent.programmingScore;
score = (newStudent.testScore + newStudent.programmingScore) / 2;
if (score >= 90)
newStudent.courseGrade = 'A';
else if (score >= 80)
newStudent.courseGrade = 'B';
else if (score >= 70)
newStudent.courseGrade = 'C';
else if (score >= 60)
newStudent.courseGrade = 'D';
else
newStudent.courseGrade = 'F';
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

10. Assignment
Value of one struct variable can be assigned to another struct variable of the same type using an assignment statement
The statement:
student = newStudent;
copies the contents of newStudent into student
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

11. Assignment (continued)
The assignment statement:
student = newStudent;
is equivalent to the following statements:
student.firstName = newStudent.firstName;
student.lastName = newStudent.lastName;
student.courseGrade = newStudent.courseGrade;
student.testScore = newStudent.testScore;
student.programmingScore = newStudent.programmingScore;
student.GPA = newStudent.GPA;
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

12. Comparison (Relational Operators)
Compare struct variables member-wise
No aggregate relational operations allowed
To compare the values of student and newStudent:
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

13. Input/Output No aggregate input/output operations on a struct variable
Data in a struct variable must be read one member at a time
The contents of a struct variable must be written one member at a time
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

14. Exercise 1
Define a struct workerType that have 5 variables or members. It is name, staffID, age, salary and depatmentName.
2. Write a main program that will:
a) declare two struct variable which is worker1 and worker2.
b) input a details for worker1.
c) assign the given value for worker2.
d) display name and staff id of the worker that have more salary
e) display the details for worker1.
Variables
Value
name
Rohaya Alias
staffID
3451
age 32
salary
4500
departmentName
Finance
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

15. Exercise 2
1)Write a struct definition called studentRec that have 7 variables/data member. The data member for this struct are name, matric number, quiz mark, test mark, final mark and total mark. 2)Write a main program that will: a) Declare one struct variable called student. b) Input name, matric number, quiz mark, test mark and final mark. c) Calculate the total mark by using the given formula: Total mark= 20% of quiz mark + 20% of test mark + 60% of final mark

16. Exercise (cont.)
d) Display the details of the student as below: ********************************* Name : XXXXXX Matric Number:XXXXXX Total Mark :XXXXXXX
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

17. struct Variables and Functions
A struct variable can be passed as a parameter by value or by reference
A function can return a value of type struct
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

18. Programing Example (struct involve function)
struct studentType {
char firstName[20];
char lastName[20];
char courseGrade;
int testScore;
int programmingScore;
double GPA; };
void inputData(studentType &s);
void main()
studentType newStudent;
newStudent.GPA = 0.0;
strcpy(newStudent.firstName,"John");
strcpy(newStudent.lastName,"Brown");
inputData(newStudent);
cout<<"\nCourse Grade for newStudent:“
<<newStudent.courseGrade;
cout<<"\nfirstName for newStudent:"<<newStudent.firstName; }
void inputData(studentType &s)
{ cout<<"Course Grade:";
cin>>s.courseGrade;
cout<<"\nProgramming Score:";
cin>>s.programmingScore;
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

19. Exercise 1
Define a struct workerType that have 5 variables or members. It is name, staffID, age, salary and depatmentName.
2. Write a main program that will:
a) declare two struct variable which is worker1 and worker2.
b) call all the functions
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

20. Exercise 1(continue)
3. Write 4 functions that will: a) input a details for worker1 and return the struct variable by using parameter by reference . b) assign the given value for worker2 and return the struct variable by using parameter by reference .
Variables
Value
name
Rohaya Alias
staffID
18225
age 32
salary
4500
departmentName
Finance
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

21. Exercise 1(continue)
c) display name of the worker that have more salary -this function will receive two struct variable d) display the details for worker1. -this function will receive one struct variable
C++ Programming: From Problem Analysis to Program Design, Fourth Edition

22. Exercise2(function) Items Prices/Unit Plain egg RM1.50 Muffin RM2.00
Write a C++ program to help a local restaurant owner to automate his/her breakfast billing system. The program should do the following tasks:
Show the customer the different breakfast items offered by the restaurant.
Allow the customer to select one item and the amount of item purchased from the menu.
Calculate and print the bill.
Assume that the restaurant offers the following breakfast items:
Items
Prices/Unit
Plain egg
RM1.50
Muffin
RM2.00
French toast
RM2.50
Fruit Basket
RM3.00

23. Exercise3(function)..Continued..
Your program must contain at least the following functions:
Function showMenu: this function shows the different items offered by the restaurant and tells the user how to select the items.
Function CalculateTotal: this function calculates the total price to be paid by the customer. The total price should include a 5% tax.
Function printCheck: this function prints the check.
Your program should use a structure to store information about the customer’s purchase: menu item, item price, the amount of item, tax value and the total amount due.
 A sample output is as follows:
Thanks for dining at Jonny’s Place
Plain egg 2 RM3.00
Tax RM0.15
 Amount Due RM3.15
C++ Programming: From Problem Analysis to Program Design, Fourth Edition