Thread: getting a function to return to main??

how do i get my fuctions to return back to main. when it runs my function ends e.g. the member_list function after operation i want it to go back to main because thats where my menu is the program is supposed to finsih when the user presses 5.

can anyone tell me then how i get my function to return to main.

ive tried putting the menu outside main but i get errors

Code:

#include <iostream.h>
#include <stdlib.h>
#include <string>
#include <fstream.h>

const int maxmembers = 15;
const int maxbooks = 30;

struct cust
{
  string surname;
  string house_no;
  string road;
  string ID;
  int books_borrowed;
};

struct books
{
  string author;
  string title;
  string category;
  string ISBN;
  int loaned;
}; 

int member_list(cust c[])
{
 for(int i=0; i< maxmembers;i++)
    {
  cout<< "Surname\t\tHouse No\tRoad\t\tID" << endl;
  cout << c[i].surname;
  cout << c[i].house_no;
  cout << c[i].road;
  cout << c[i].ID << endl;
    }
}

int book_list(books b[])
{
 for(int i=0; i< maxbooks;i++)
    {
  cout<< "Author\t\t\tTitle\t\t\tCategory\tISBN" << endl;
  cout << b[i].author ;
  cout << b[i].title ;
  cout << b[i].category;
  cout << b[i].ISBN << endl;
    }
}

void issue_book(books b [], cust c[])
{
  string  member = 0;
  string ISBN = 0;
  cout << "Please enter ISBN number of book: " << endl;
  cin >> ISBN ;
  cout << "Please enter member ID: " << endl;
  cin >> member;
  for(int i=0; i < maxbooks; i++)
    {
      if (b[i].ISBN == ISBN)
	{
	  b[i].loaned ++;
	}
    }

  for(int i=0; i < maxmembers; i++)
    {
      if(c[i].ID == member)
	{
	  c[i].books_borrowed ++;
	}
    }
  //save_book(b);
  //save_user(c);
}
  
void return_book(books b[], cust c[])
{
  string member = 0;
  string ISBN = 0;
  cout << "Please enter ISBN number of book: " << endl;
  cin >> ISBN ;
  cout << "Please enter member ID: " << endl;
  cin >> member;
  for(int i=0; i < maxbooks; i++)
    {
      if (b[i].ISBN == ISBN)
	{
	  b[i].loaned --;
	}
    }
  for(int i=0; i < maxmembers; i++)
    {
      if(c[i].ID == member)
	{
	  c[i].books_borrowed --;
	}
    }
  //save_book();
  //save_user();
  
}

/*void save_book(books b[])
{
ofstream book_data;

 if (book_data.is_open())
   {
for(int i=0; i < maxbooks;i++)
  {
  book_data << b[i].author;
  book_data << ";";
  book_data << b[i].title;
  book_data << ";";
  book_data << b[i].category;
  book_data << ";";
  book_data << b[i].ISBN;
  book_data << ";";
  book_data << b[i].loaned;
  book_data << ";";
  }
 book_data.close();
   }
}*/


/*void save_user(cust c[])
{
ofstream user_data;

if (user_data.is_open())
  {
    for(int i=0; i < maxmembers;i++)
      {
 user_data << c[i].surname;
 user_data << ";";
 user_data << c[i].house_no;
 user_data << ";";
 user_data << c[i].road;
 user_data << ";";
 user_data << c[i].ID;
 user_data << ";";
 user_data << c[i].books_borrowed;
 user_data << ";";
  }
	user_data.close();
	{
}*/

int main()
{

//variables for type people and books
  books book[maxbooks];
  cust user[maxmembers];

  char uTest[1000];
  int cRead = 0;
  int nTest = 100;

  ifstream user_data;
  user_data.open("userdata.txt",ios::in);

do
  {
    user_data.getline(uTest,nTest,';');
    user[cRead].surname = uTest;
    user_data.getline(uTest,nTest,';');
    user[cRead].house_no = uTest;
    user_data.getline(uTest,nTest,';');
    user[cRead].road = uTest;
    user_data.getline(uTest,nTest,'\n');
    user[cRead].ID = uTest;

    if (user_data)
      {  int nTest[100];
	cRead++;
      }

  }while (user_data && cRead < maxmembers);

  user_data.close();

  ifstream book_data;
  book_data.open("bookdata.txt",ios::in);

do
  {
    book_data.getline(uTest,nTest,';');
    book[cRead].author = uTest;
    book_data.getline(uTest,nTest,';');
    book[cRead].title = uTest;
    book_data.getline(uTest,nTest,';');
    book[cRead].category = uTest;
    book_data.getline(uTest,nTest,'\n');
    book[cRead].ISBN = uTest;

    if (book_data)
      {
	cRead++;
      }

  }while (book_data && cRead < maxbooks);

  book_data.close();

  int choice;
  cout <<"Library Menu" << endl << endl ;
  cout <<"[1] List Library Members and Member Information" << endl;
  cout <<"[2] List Library Books and Book Information" << endl ;
  cout <<"[3] Issue Library Book" << endl ;
  cout <<"[4] Return Library Book" << endl ;
  cout <<"[5] Exit Library System" << endl ;
  cout <<"Enter Your Required Choice" << endl;
  cin >> choice;
  
  switch(choice)
    {
    case 1:
      member_list(user);
      break;
    case 2:
      book_list(book);
      break;
    case 3:
      issue_book(book,user);
      break;
    case 4:
      return_book(book,user);
      break;
    case 5:
      exit(1);
      break;
    default:
      cout << "This is not an option" << endl;
      break;
    
    }
}