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Function is not incrementing correctly

beethekid (6)
Background information:
- member is a vector of pointers to Student objects
- m is a student object
- I am trying to add pointers that point to a Student object as long as the name for that Student object has not been added already.

In my add_member program in StudentClub.cpp, here are the steps I took. There's clearly something wrong with the incremementation and creating the member vector but I can't figure out what it is.

1. I created a for loop to check each element of the vector against the name of the member object (the name is collected using getline in the main function) to see if there are any matches.
2. If there is a match, this means that the name has already been recorded so the function can be ended (so I put a return)
3. If there is no match, then the object can be pushed back into the member vector since there is no repeat and they are a new member.

I'm sure the mistake is in the definition of the function, but I also included a part of my main function. If you need any more information, just let me know! 


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//This is the function declaration of add_member in StudentClub.cpp
 #include "StudentClub.h"
#include <iostream>
#include <vector>
#include "Student.h"

using namespace std;

void StudentClub::add_member(Student* m)
{
    for (int i = 0; i < member.size(); i++)
    {
        if (m->name == member[i]->name)
        {
            return;
        }
    }
    member.push_back(m);
}



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//This is the main function
#include <iostream>
#include "Student.h"
#include "StudentClub.h"
#include <vector>
#include <iomanip>

using namespace std;

int main()
{
    Student p,v,s,t,m;
    vector <Student*> clubmem;
    StudentClub club (&p, &v, &s, &t, clubmem);
    
    cout << "President: ";
    getline (cin,p.name);
    cout << endl;
    

    
    cout << "Vice-President: ";
    getline (cin,v.name);
    cout << endl;

    
    
    cout << "Secretary: " ;
    getline (cin,s.name);
    cout << endl;

    
    
    cout << "Treasurer: ";
    getline (cin,t.name);
    cout << endl;

//if Q is typed by the user, then the function is exited 
while(m.name != "Q")
    {
       cout << "New Member (Q to quit): ";
       getline(cin, m.name);
       cout << endl;
       if (m.name != "Q")
       {
           club.add_member(&m);
       }
    }
    
    club.add_member(&p);
    club.add_member(&v);
    club.add_member(&s);
    club.add_member(&t);

Last edited on
ne555 (10692)
> If you need any more information, just let me know!
so, ¿what's the problem? ¿no member is added? ¿you've got repeated members? ¿how are you checking that?
post enough code in order to reproduce your problem.

>member is a vector of pointers to Student objects
¿why pointers?

club.add_member(&m);
&m will not change, you pass the same pointer in every iteration of the loop
beethekid (6)
member is a vector of pointers to Student objects - Why pointers?
Its an assignment and its part of the specs so unfortunately I have to keep member as a vector of pointers.

club.add_member(&m);
&m will not change, you pass the same pointer in every iteration of the loop

Thank you; I see that now! Is there any way to ensure that &m changes with every iteration of the loop.
seeplus (6591)
There's a couple. Possibly the easiest is to keep a vector of members (std::vector<std::string>), add members to this in the loop and call cliub.add_member with the address of the element in the vector as it's added. You can also do it using dynamic memory (using new /delete). When you store a pointer to something then the 'something' has to exist as long as the pointer is to be used.
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