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Need help with class implementations

InfiniteLoop (16)
I'm trying to write a student class registration program that uses three classes: class Course, class Student, and class Wrapper(to eliminate the need for global declarations). I've written them out, but I'm getting all sorts of errors. I have no idea how to fix them. :(

Errors:

homework3.h:29 multiple types in one declaration
homework3.h:45 expected primary-expression before '.' token
At global scope:
homework3.h:55 multiple types in one declaration
homework3.h:155 'class Course' has no member named 'getname'
homework3.h:184 'class Course' has no member named 'getname'
homework3.h:185 'class Course' has no member named 'getprofessor'


Header file:
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#ifndef WRAPPER_H
#define WRAPPER_H
#include <iostream>
#include <list>
using namespace std;

class Course

class Student
{
    typedef list<Course *>::iterator citerator;
    
    public:
        Student (string n): nameText(n) { }
        string getWaitList() {return waitlist;}
        //operations
        string name() {return nameText;}
        void addCourse(Course * c) {courses.push_back(c);}
        citerator firstCourse() {return courses.begin();}
        citerator lastCourse() {return courses.end();}
        void removeCourse (citerator & citer) {courses.erase(citer);}
        
    private:
        string waitlist;
        string nameText;
        list <Course * > courses;
        
        //friend class Wrapper
};


class Student

class Course
{
    friend class Wrapper;
    
    public:
        Course(string n, int s, string p, string c):name(n), max(s), 
            professor(p), classroom(c) { }
        Course(string n, int s):name(n), max(s) { }
        string getName() {return name;}
        string getProfessor() {return professor;}
        string getClassroom() {return classroom;}
        bool full() {return Student.size()>=max;}
        void addStudent (Student * s) {students.push_back(s);}
        void generateClassList();
        
    private:
        string professor;
        string classroom;
        string name;
        int max;
        list <Student *> students;
};

class Wrapper
{
	public:
		Wrapper();
		Wrapper(list <Course *> course, list <Student *> student);
		void readStudents(istream & infile);
		void fillCourses();
		Student * findStudent (string & searchName);
		Course * findCourse (string & searchName);
		string getwname() { return wname; };
		void readCourses(istream & infile);
		void generateCourseReports();
		void generateStudentReports();
	protected:
		string wname;
		string professor;
		string classroom;
		list <Student *> all_students;
		list <Course *> all_courses;
};
Wrapper::Wrapper()
{
	all_students;
	all_courses;
}
void Wrapper::readCourses(istream & infile)
{
	string name;
	int max;
	string professor;
	string classroom;
	while (infile >> name >> max >> professor >> classroom)
	{
		Course * newCourse = new Course (name, max, professor, classroom);
		all_courses.push_back(newCourse);	
	}
}
void Wrapper::readStudents(istream & infile)
{
	string name;
	string course;
	while (infile >> name >> course)
	{
		Student * theStudent = findStudent(name);
		Course * theCourse = findCourse(course);	
		
		if (theCourse != 0)
		{
			theStudent -> addCourse(theCourse);
		}
		else
			cout << "student " << name << " requested invalid course " <<
                course << endl;
	}
}
void Wrapper::fillCourses()
{
	list<Student *>::iterator s_start, s_end;
	s_start = all_students.begin();
	s_end = all_students.end();
	
	for ( ; s_start != s_end; ++s_start)
	{
		list<Course *>::iterator c_start, c_end, c_next;
		c_start = (*s_start) -> firstCourse();
		c_end = (*s_start) -> lastCourse();
		for ( ; c_start != c_end; c_start = c_next)
		{
			c_next = c_start; ++c_next;
			if (!(*c_start) -> full())
				(*c_start) -> addStudent(*s_start);
			else
				(*s_start) -> removeCourse(c_start);
		}
	}
}
Student * Wrapper::findStudent (string & searchName)
{
	list <Student *>::iterator start, stop;
	start = all_students.begin();
	stop = all_students.end();
	for ( ; start != stop; ++start)
	{
		if ((*start) -> name() == searchName)
			return *start;
	}
		//if not found, make one
	Student * newStudent = new Student(searchName);
	all_students.push_back(newStudent);
	return newStudent;
}
Course * Wrapper::findCourse (string & searchName)
{
	list <Course *>::iterator start, stop;
	start = all_courses.begin();
	stop = all_courses.end();
	for ( ; start != stop; ++start)
	{
		if ((*start) -> getname() == searchName)
			return *start;
	}
		//if not found, make one
	Course * newCourse = new Course(searchName, NULL);
	return newCourse;
}
void Wrapper::generateCourseReports()
{	
	list <Course *>::iterator start, stop;
        start = all_courses.begin();
        stop = all_courses.end();
        for ( ; start != stop; ++start)
                (*start) -> generateClassList();
}
void Wrapper::generateStudentReports()
{
	list <Student *>::iterator s_start, s_stop;
	list <Course *>::iterator c_start, c_stop;
	s_start = all_students.begin();
	s_stop = all_students.end();
	
	for ( ; s_start != s_stop; ++s_start)
	{
		cout << endl;
		cout << "Class list for " << (*s_start)->name() << ":" << endl << endl;
		c_start = (*s_start) -> firstCourse();
		c_stop = (*s_start) -> lastCourse();
		for ( ; c_start != c_stop; ++c_start)
			cout << (*c_start) -> getname() << " with professor " << 
                (*c_start) -> getprofessor() << endl;
	}
}

#endif


.cpp file.
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#include "homework3.h"
#include <iostream>
#include <list>
//#include "Wrapper.h"
//#include "Student.h"
//#include "Course.h"
using namespace std;

bool studentCompare(Student * a, Student * b)
{
    return a->name()>b->name();
}

void Course::generateClassList()
{
    students.sort(studentCompare);
    cout<<endl<<"Class list for "<<getName()<<" with Professor "<<
        getProfessor()<<" in class "<<getClassroom()<<":"<<endl;
    list<Student *>::iterator start, stop;
    start=students.begin();
    stop=students.end();
    for( ; start!=stop;++start)
    {
        cout<<(*start)->name()<<endl;
    }
}
LB (13399)
Line 7: Missing semicolon

Why are you using std::list instead of std::vector? It's horribly inefficient in most cases (such as this case).

Line 32: Pointless forward declaration, also missing semicolon.

Also, why are you using pointers for everything?

Your main problem is that you've got full definitions in your header file - either define them inline (inside the class defintion) or move them to the .cpp source file. Full function definitions don't belong in headers unless they're trivial.
Last edited on
InfiniteLoop (16)
Thanks. I got rid of most of the problems. I split the classes into separate files and put all the member functions into the .cpp file.

The professor wants us to use list. And the assignment was to take a program from the book and improve it, so the abundance of pointers wasn't my idea. :P

Now there's just one error:

Course.h:22 expected primary-expression before '.' token


for this line:

 
 
bool full() {return Student.size()>=max;}
long double main (999)
Did you mean bool full() { return students.size() >= max; }?
InfiniteLoop (16)
Yeah, I did mean that. XD

Now I'm getting a linker error!

In function `main'::
[Linker Error] undefined reference to `WinMain@16'
ld returned 1 exit status


There's also this warning:

In member function 'Course* Wrapper::findCourse(std::string&)':
91:50 [Warning] passing NULL to non-pointer argument 2 of 'Course::Course(std::string, int)' [-Wconversion-null]


It doesn't seem to like the NULL is this function:
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Course * Wrapper::findCourse (string & searchName)
{
	list <Course *>::iterator start, stop;
	start = all_courses.begin();
	stop = all_courses.end();
	for ( ; start != stop; ++start)
	{
		if ((*start) -> getName() == searchName)
			return *start;
	}
		//if not found, make one
	Course * newCourse = new Course(searchName, NULL);
	return newCourse;
}


Help?
long double main (999)
About the first message (the linker error): do you have a main function?

For the second (the warning): you're passing NULL (which is typically used for pointers) to an int parameter (representing the max size of the class, it seems).
What does it mean for the max size to be "null"?
InfiniteLoop (16)
._. Now it compiles.

I hate asking, but can I see some example code for how to apply this data to the main function? I'm completely clueless when it comes to the fstream library.

Course.txt
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ART101 4 Ted UH200
HIST213 3 Joan CS110
MATH412 2 Jackie JBH389
CSCI330 3 Joe JBH146


Student.txt
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Smith,Amy ART101
Smith,Amy MATH412
Jones,Randy HIST213
Cobb,Kevin MATH412
Mo,Jo CSCI330
Smith,Kathy CSCI330
Jones,Randy CSCI330
Smith,Kathy MATH412
Smith,Kathy ART101
Cobb,Kevin CSCI330
No,No CSCI330
No,No MATH412
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