using linked list

[ykfc]

Although I've programmed a lot in different languages but I'm new to VC++. A typical requirement is: I need to build a list for some customers. Each customer record has a list of item purchased. So I think I could define a customer record as:

typedef struct CustRcd {
char *name;
int num_purchases;
struct Purchases *purchased_item;
//points to the first item
struct CustRcd *nextCust;
} CustRcd;

typedef struct Purchases {
char purchaseItemName[LINESIZE];
struct Purchases *nextItem;
} Purchases;

Assume a customer could be appended to the list before making the first purchase. Question is: should I make purchased_item point to NULL when the customer has not purchased anything? I have tried to use this method but I experienced some problems. Eventually I end up a solution by making each newly added customer purchase one dummy item!! I think I've missed something but still struggling with no idea. Can someone enlighten me?

If the above question is hard to comprehen, can someone point me to a link (something like a tutorial/exercise with an answer) where it could show me how codes should be structured? Thanks a lot.

 

[PerFnurt]

>I need to build a list for some customers

You can have a list for free by using STL. You can also get string management for free.

#include <list>
#include <string>

struct Purchase {
    std::string mName; 
};

typedef std::list<Purchase> Purchases;

struct Customer {
    std::string mName;
    Purchases mPurchases; 
} ;

typedef std::list<Customer> Customers;

See

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclang98/HTML/LIST_list.asp

for info on what you can do with it.


/Per

_{"It was a work of art, flawless, sublime. A triumph equaled only by its monumental failure."}

 

[teriviret]

I would set purchased_item to NULL if the customer hasn't purchased anything. What problems did you get into by doing this? I'm thinking, maybe when you access purchased_item in other parts of the code, you aren't checking for NULL before trying to dereference it?