Function add linked list

Hello
I use 2 linked list
===> Doctor
===>student
the First doctor A, has three students Student_1, Student_2 and Student_3.

the second doctor B, has one students Student_4.
the Third doctor C, has one students Student_5.

to linked student, i using this function:

Code:

---

    Doctor * Doct;
    student *st1, *st2;

    Doct = new Doctor;
        Doct->Do = "A";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_1";
        st2 = new student;
        st2->next = st1;
        st2->St = "Student_2";
        st1 = st2;
        st2 = new student;
        st2->next = st1;
        ptr_t->add_tasks(Doct);

        Doct->Do = "B";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_3";
        Doct->Stu = st1;
        ptr_t->add_tasks(Doct);

        Doct->Do = "C";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_4";
        Doct->Stu = st1;
        ptr_t->add_tasks(Doct);

---

How do I create a function add_student ,Instead of this primitive method .

Code:

---

#include <iostream>
#include <string>
using namespace std;

struct student
{
    string  St;
    student * next;
};
class student_Un
{

    private:
        student *first;
    public:
        ~student_Un();
        student_Un();
        void add_student(student *p);
        void gener_student();

};
/* ------------------------------------------*/
struct Doctor
{
    string Do;
    student * Stu;
    Doctor * next;
};
class Doctor_Un
{

    private:
        Doctor *first;
    public:
        ~Doctor_Un();
        Doctor_Un();
        void add_tasks(Doctor *p);
        void gener_tasks();
};
/* ------------------------------------------*/
Doctor_Un :: ~Doctor_Un()
{
    typedef struct Doctor t;
    t * ptr;
    t * qtr;
    ptr = first;
    qtr = first->next;
    while (ptr)
    {
        delete ptr;
        ptr = qtr;
        if (! qtr)
        {
            qtr = qtr->next;
        }
    }
}

/* ------------------------------------------*/
Doctor_Un ::Doctor_Un()
{
    first=NULL;
}
/* ------------------------------------------*/

void Doctor_Un :: add_tasks(Doctor *p)
{
    Doctor * ptr;
    ptr = new Doctor;
    *ptr = *p;
    if(first == NULL)
    {
        ptr->next = NULL;
    }
    else
    {
        ptr->next = first;
    }
    first = ptr;
}

/* ------------------------------------------*/

void Doctor_Un :: gener_tasks()
{
    Doctor * ptr;
    for(ptr = first; ptr ; ptr = ptr->next)
        cout<< ptr->Do << '\t';
    cout<<'\n';
}
/* -------------------------------------------- */
void allocate( Doctor_Un * ptr_t)
{

    Doctor * Doct;
    student *st1, *st2;

    Doct = new Doctor;
        Doct->Do = "A";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_1";
        st2 = new student;
        st2->next = st1;
        st2->St = "Student_2";
        st1 = st2;
        st2 = new student;
        st2->next = st1;
        ptr_t->add_tasks(Doct);

        Doct->Do = "B";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_3";
        Doct->Stu = st1;
        ptr_t->add_tasks(Doct);

        Doct->Do = "C";
        st1 = new student;
        st1->next = NULL;
        st1->St = "Student_4";
        Doct->Stu = st1;
        ptr_t->add_tasks(Doct);



    cout << "************************************************************************** \n";
    ptr_t->gener_tasks();


}

/* -------------------------------------------- */

int main(int argc, char** argv)
{

    Doctor_Un * ptr_t;

    ptr_t = new Doctor_Un;



    allocate(ptr_t);

  int x;
  cin >> x;
 
  return 0;
}

---

Sorry but i can't figure out what you are trying to do. The whole thing is primitive. Why not use std::list and not worry about the design of the linked list itself?
http://cplusplus.com/reference/stl/list/

if you really want to make your own singly linked list I suggest that you create a really simple template class that works with integers first and get that working. Once you have a template class in place it ought to work with any other type. I also suggest that you do a web search. There are many linked list examples. The code that you posted is very confusing.

Quote:

---

Originally Posted by kempofighter

Sorry but i can't figure out what you are trying to do. The whole thing is primitive. Why not use std::list and not worry about the design of the linked list itself?
http://cplusplus.com/reference/stl/list/

if you really want to make your own singly linked list I suggest that you create a really simple template class that works with integers first and get that working. Once you have a template class in place it ought to work with any other type. I also suggest that you do a web search. There are many linked list examples. The code that you posted is very confusing.

---

when I put second Doctor, Students take from the first Doctor
as,

Doctor 1
===> Student 1
===> Student 2

Doctor 2
===> Student 1
===> Student 2
===> Student 3
===> Student 4

Now, How do I create a function add_student?

Quote:

---

Originally Posted by NewLegend2

when I put second Doctor, Students take from the first Doctor
as,

Doctor 1
===> Student 1
===> Student 2

Doctor 2
===> Student 1
===> Student 2
===> Student 3
===> Student 4

Now, How do I create a function add_student?

---

I have no idea what that first statement means. Again - please state your requirements more clearly. What do you want a linked list of? students? Doctors? Both?

Quote:

---

Originally Posted by kempofighter

I have no idea what that first statement means. Again - please state your requirements more clearly. What do you want a linked list of? students? Doctors? Both?

---

I used 2 linked list.

First : Students.
Second: Doctor.

Every Doctor takes a set of his students.
as,
Doctor 1
===> Student 1
===> Student 2

Doctor 2
===> Student 3
===> Student 4



In this code:
when I put second Doctor, Students take from the first Doctor
as,
Doctor 1
===> Student 1
===> Student 2

Doctor 2
===> Student 1
===> Student 2
===> Student 3
===> Student 4

[ removed duplicate thread ]

Please do not start multiple threads on the same topic.