1. Student Data Score First Name Last Name ID GPA DOB Phone ...
How to store student data in our programs?

2. Store Student Data in Variables
// For one student at a time
float score, GPA;
string firstName, lastName, ID; …

3. Store Students Data in Parallel Arrays
const int MAX_SIZE = 30;
// To keep data for all students
float scores[MAX_SIZE], GPA[MAX_SIZE];
string firstName[MAX_SIZE], lastName[MAX_SIZE],
ID[MAX_SIZE];

4. C++ Structure struct Student { string id; string firstName, lastName;
float gpa; };
// Student is a data type!

5. Structure Variables int numStudents; float score; Student s1, s2;
// Student is a data type!

6. Accessing Members of a Structure Variable
Student s1;
// Input data into struct
cout << "Enter ID: ";
cin >> s1.id;
cout << "Enter first name: ";
cin >> s1.firstName;
// Output student data
cout << setw(9) << s1.id
<< setw(25) << s1.firstName;
Using the dot notation!

7. C++ Class class Student { string id; string firstName, lastName;
float gpa; };
// Student is a class (data type)!
// By default, all fields are private.

8. Create public functions (methods) to access private fields.
C++ Class
class Student {
private:
string id;
string firstName, lastName;
float gpa;
public:
. . . };
Create public functions (methods)
to access private fields.

9. Class Methods class Student { private: string id;
string firstName, lastName;
float gpa;
public:
// Make sure the order is correct.
void Read()
cin >> id >> firstName >> lastName
>> gpa; } };

10. Class Methods class Student { private: string id;
string firstName, lastName;
float gpa;
public:
void Read()
void Print()
cout << endl;
cout << setw(9) << id << setw(20) << firstName
<< setw(20) << lastName << setw(5) << gpa; } };

11. Calling Class Methods Using the dot notation! Student s1;
// Input data into object s1
s1.Read();
// Output data of object s1
s1.Print();
Using the dot notation!

12. Syntax and Style class Student { private: string id;
string firstName, lastName;
float gpa;
public:
void Read()
. . . };
// class, private, public: key word
// Student: Identifier, your choice
// Fields : Declaring variables
// Braces
// Semicolon after }
// Read, Print: class methods (function inside class)
// Indentation

13. Semantics Student is a new data type!
class Student {
private:
string id;
string firstName, lastName;
float gpa;
public:
void Read()
cin >> id >> firstName >> lastName
>> gpa; }
. . . };
Student is a new data type!
It has data fields and methods (functions) on the data.

14. Semantics
class Student {
private:
string id;
string firstName, lastName;
float gpa;
public:
void Read()
cin >> id >> firstName >> lastName
>> gpa; }
. . . };
Data fields have class scope and can be accessed from any class methods!

15. C++ Classes cin >> base;
while ( !cin.eof() && (base < 2 || base > 9) ) {
// display message
cin.ignore(MAX_LINE_SIZE, ‘\n’);
cin >> base: }

16. More Class Methods class Student { private: . . . public:
string getFirst()
return firstName; }
void setFirstName( string name )
firstName = name; };

17. More Class Methods class Student { private: . . . public:
string getGPA()
return gpa; }
void setGPA( float value )
gpa = value;
void updateGPA( float amount )
gpa += amount; };

18. Calling Class Methods // Comparing two students
if ( s1.getGPA() > s2.getGPA() )
cout << “\nFirst student has higher GPA.";
else if ( s1.getGPA() < s2.getGPA() )
cout << “\nSecond student has higher GPA.";
else
cout << “\nThe two student have the same GPA.";

19. Calling Class Methods // Updating students data s1.setGPA( 2.9 );
s1.updateGPA( 0.5 );
if ( s1.getGPA() > s2.getGPA() )
cout << “\nFirst student has higher GPA.";
else if ( s1.getGPA() < s2.getGPA() )
cout << “\nSecond student has higher GPA.";
else
cout << “\nThe two student have the same GPA.";

20. class Student {
. . . }
int main()
Student s1, s2;
s1.Read();
s2.Read();
s1.Print();
s2.Print();
// Comparing GPA of s1 and s2
s1.updateGPA( 0.5 );
return 0;

21. //----------------------------------------
// Comment Block
// Includes
// constants
class Student {
. . . }
// Function prototypes
int main()
return 0;
// Function definitions

22. Wednesday: Test2 Review
Schedule
Quiz5-5: Due today
Quiz7-1: Due Wednesday
Wednesday: Test2 Review
Thursday: Lab 8
Friday
Test 2: 60 points
Notes
Program 4
Due Wednesday, April 6
Grace Friday, April 8

23. Quiz5-6 Now