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#include <iostream>
using namespace std;

struct subject;
struct SJ_Node;
struct ListSubjects;

struct subject{
    string ID_SJ;
    string name_SJ;
    int number_credit_SJ;
    float GK, CK;
    float Process_weight;  // Trong so qua trinh
    float FinalExam_weight; // Trong so cuoi ki
    subject(string ID, string name, int credit, float process, float final, int gk, int ck):
        ID_SJ(ID), name_SJ(name), number_credit_SJ(credit), Process_weight(process), FinalExam_weight(final), GK(gk), CK(ck){};
};

struct SJ_Node{
    subject SJ_infor;
    SJ_Node* prev;
    SJ_Node* next;
    SJ_Node (subject sj): SJ_infor(sj){};
};

struct ListSubjects{
    SJ_Node* Head;
    ListSubjects () : Head(NULL) {};
    // Bo sung mon hoc cho sinh vien
    void InsertAfter(string ID, subject sj){
        SJ_Node* run = Head;
        while (run){
            if (run->SJ_infor.ID_SJ == ID){
                SJ_Node* newNode = new SJ_Node(sj);
                newNode->next = run->next;
                run->next = newNode;
                return;
            }
            run = run->next;
        }
        // If the list is empty or the ID is not found, create a new node at the beginning
        SJ_Node* newNode = new SJ_Node(sj);
        newNode->next = Head;
        Head = newNode;
    }
};

struct student;
struct Student_Node;
struct ListStudents;

struct student{
    long int ID_Student;
    string name_Student;
    string class_Student;
    ListSubjects List_Subject_ofStudent;
    student(long int ID, string name, string classs, ListSubjects listSJ): 
        ID_Student(ID), name_Student(name), class_Student(classs), List_Subject_ofStudent(listSJ){};
};

struct Student_Node{
    student Student_infor;
    Student_Node* prev;
    Student_Node* next;
    Student_Node (student sv): Student_infor(sv) {};
};

struct ListStudents{
    Student_Node* Head;
    ListStudents (): Head(NULL) {};
    bool IsEmpty(){
        cout << "empty" << endl;
        return Head == NULL;
    }
    // Bo sung sinh vien vao dau danh sach
    void InsertBegin(student sv){
        Student_Node* newNode = new Student_Node(sv);
        if (!Head){
            Head = newNode;
        }else{
            newNode->next = Head;
            Head->prev = newNode;
            Head = newNode;
        }
    }
    // Bo sung sinh vien vao sau sinh vien co mssv cho truoc
    void InsertAfter(int ID, student sv) {
        if (IsEmpty()) return;
        Student_Node* run = Head;
        while (run != NULL) {
            if (run->Student_infor.ID_Student == ID){
                Student_Node* newNode = new Student_Node(sv);
                newNode->next = run->next;
                run->next = newNode;
                return;
            }
            run = run->next;
        }    
    }
    // Tim kiem sinh vien theo mssv cho truoc
    Student_Node* SearchByID(int ID){
        Student_Node* run = Head;
        if (IsEmpty()) return NULL;
        while(run != NULL){
            if (run->Student_infor.ID_Student == ID){
                return run;
            }
            run = run->next;
        }
        cout << "No exists ID" << ID << endl;
        return NULL;
    }
    // Tinh diem tich luy tat ca cac sinh vien trong danh sach
    float CalculateAll(){
        if (IsEmpty()) return -1;
        float mark = 0;
        Student_Node* run = Head;
        while (run != NULL) {
            mark += CalculateByID(run->Student_infor.ID_Student);
            run = run->next;
        }
        return mark;
    }
    // Tinh diem tich luy cua mot sinh vien cho truoc
    float CalculateByID(int ID){
        if (IsEmpty()) return -1;
        Student_Node* run = Head;
        while(run != NULL){
            if (run->Student_infor.ID_Student == ID){
                ListSubjects list = run->Student_infor.List_Subject_ofStudent;
                SJ_Node* run = list.Head;
                float mark = 0;
                int cntSJ = 0;
                while (run){
                    float GK = run->SJ_infor.GK * run->SJ_infor.Process_weight;
                    float CK = run->SJ_infor.CK * run->SJ_infor.FinalExam_weight;
                    mark += GK + CK;
                    cntSJ++;
                    run = run->next;
                }
                float res = mark/cntSJ;
                return res;
            }
            run = run->next;
        }
        cout << "No exists ID" << ID << endl;
        return -1;        
    }
};



int main(){
        // Create a list of subjects
    ListSubjects subjectsList;
    subjectsList.InsertAfter("1", subject("S1", "Math", 3, 0.3, 0.7, 8, 9));
    subjectsList.InsertAfter("2", subject("S2", "Physics", 4, 0.4, 0.6, 7, 8));
    subjectsList.InsertAfter("3", subject("S3", "Chemistry", 3, 0.3, 0.7, 9, 7));

    // Create a list of students
    ListStudents studentsList;
    studentsList.InsertBegin(student(1, "John", "ClassA", subjectsList));
    studentsList.InsertBegin(student(2, "Jane", "ClassB", subjectsList));
    studentsList.InsertBegin(student(3, "Bob", "ClassC", subjectsList));

    // Calculate and display the total marks for all students
    float totalMarks = studentsList.CalculateAll();
    cout << "Total Marks for all students: " << totalMarks << endl;

    // Calculate and display the average marks for a specific student (e.g., ID 1)
    int studentID = 1;
    float averageMarks = studentsList.CalculateByID(studentID);
    if (averageMarks != -1) {
        cout << "Average Marks for Student ID " << studentID << ": " << averageMarks << endl;
    }

    return 0;    
}