c++中类关系中的错误

我对类关系的概念很陌生，写了一个程序来测试它。然而，它给了我一些错误。

有5个头文件类别大学，部门，教师，学生和课程和一个。cpp文件涉及。我实现了大学与院系的组合，院系与学生、老师、课程的双向关联

uni.h

#pragma once
//#include"dept.h"
class University
{
public:
    University(string,int);
    void setDepartmentName(string,int);
    Dept* getDeptAddress(int);
    ~University();
private:
    Dept* departments;
    int totalDepts;
    string name;
};
University::University(string name1,int num) :name(name1)
{
departments = new Dept[num];
totalDepts=num;
}
void University::setDepartmentName(string name,int depNo)
{
departments[depNo].setName(name);
}
Dept* University::getDeptAddress(int i)
{
return &(departments[i]);
}
University::~University()
{
delete[] departments;
}

dept.h

#pragma once
//class Student;
//class Teacher;
//class Course;
#include"course.h"
#include"teacher.h"
#include"student.h"
class Dept
{
    public:
    Dept();
    string getName();
    void setName(string);
    ~Dept();
private:
    Student** students;
    Course** courses;
    Teacher** teachers;
    string name;
    int noOfStudents, noOfTeachers, noOfCourses;
};
Dept::Dept()
{
}
string Dept::getName() {
    return name;
}
void Dept::setName(string name1) {
    name = name1;
}
Dept::~Dept()
{
}

course.h

#pragma once
class Dept;
//#include"dept.h"
class Course
{
public:
    Course(string, string);
    void assignDept(Dept*);
    string getDeptName();
    ~Course();
private:
    Dept* department;
    string code;
    string name;
};
Course::Course(string code1, string name1) :code(code1), name(name1)
{} 
void Course::assignDept(Dept * dep)
{
    department = dep;
}
string Course::getDeptName()
{
//statement giving error: 'Use of undefined type 'Dept'' & 'left of -> must point to class'
    return department->getName();
}
Course::~Course()
{}

student.h

#pragma once
#include"dept.h"
class Student
{
public:
    Student(string,string);
    void assignDept(Dept*);
    string getDeptName();
    ~Student();
private:
    Dept* department;
    string rollNo, name;
};
Student::Student(string rNo,string name1):name(name1),rollNo(rNo)
{}

void Student::assignDept(Dept *dep)
{
    department = dep;
}
string Student::getDeptName()
{
//statement giving error: 'Use of undefined type 'Dept'' & 'left of -> must point to class'
    return department->getName();
}

Student::~Student()
{
}

teacher.h

#pragma once
//#include"dept.h"
class Teacher
{
public:
    Teacher(string);
    void assignDept(Dept*);
    string getDeptName();
    ~Teacher();
private:
    Dept* department;
    string name;
};
Teacher::Teacher(string name1) :name(name1)
{}

void Teacher::assignDept(Dept *dep)
{
    department = dep;
}
string Teacher::getDeptName()
{
//statement giving error: 'Use of undefined type 'Dept'' & 'left of -> must point to class'
    return department->getName();

}
Teacher::~Teacher()
{
}

source.cpp

#include<iostream>
using namespace std;
#include<string>
#include"dept.h"
#include"course.h"
#include"teacher.h"
#include"student.h"
#include"uni.h"
int main()
{
University u1("FAST",3);
u1.setDepartmentName("CS", 0);
u1.setDepartmentName("EE", 1);
u1.setDepartmentName("CV", 2);
Student s1("l144049", "Syed Abdul Wahab");
Course c1("cs1", "ITC");
Teacher t1("abc");
c1.assignDept(u1.getDeptAddress(0));
t1.assignDept(u1.getDeptAddress(1));
s1.assignDept(u1.getDeptAddress(2));
cout << c1.getDeptName()<<endl;
cout << t1.getDeptName() << endl;
cout << s1.getDeptName() << endl;
cin.get();
return 0;
}

然而，如果我#在student.h, course.h和teacher.h中包含'Dept .h'，它会给我'Dept'上的错误，即'标识符'Dept'未定义'。任何帮助我将非常感激!