Problems with c++? or template list ? or ???
Author
Well, basically I am making a blackjack game. And I wanted to give it a run with the current AI in there.
The game works as planned, however the biggest problem I notice is when I open taskmanager and watch the resources it consumes.
It's not too bad maybe 50k per few seconds, but the thing is I'm not inserting more items into any list, I am simply shuffling cards from one list to another. I have tried running the game for more than a minute then deleting all the lists and I still have a 'leak' or whatever it is.
There is a lot of computation and checking involved in the code; I guess my question is : does this computation take up memory within windows ?
Could my memory leaks be due to the fact that I am removing an item from one list and inserting into another (which probably assigns a new address ?)
I'm stumped, and I know this will be a problem if I ever decide to run more than 1mil games.
Thanks in advance
Author
Wow, now tell me if this makes sense. I am running the game to play 1million games while I was typing the above post. And when I looked at taskmanager after posting i noticed that from 2.5k resources it went to 896k, what happened?
The game is still running this is just wierd. I'm confused, anyways thanks again
The game is still running this is just wierd. I'm confused, anyways thanks again
50k sounds like quite a bit for a simple Black Jack game. What library are you using to program this?
Also, it is hard to tell you what is wrong without seeing some code. Paste some code where you think the error is at. Have you tried using software like Glowcode that will tell you where the leak is? Or, you could simply overload the new and delete operators and keep track that way.
Also, it is hard to tell you what is wrong without seeing some code. Paste some code where you think the error is at. Have you tried using software like Glowcode that will tell you where the leak is? Or, you could simply overload the new and delete operators and keep track that way.
Author
gonna try glowcode;
I think windows just took too long to update the task manager, that's why it seemed to eat up much memory.
The code has been tested for over a few hours--i'm 95% sure the code is not the problem. If my template list is bad, then that could be the problem
I think windows just took too long to update the task manager, that's why it seemed to eat up much memory.
The code has been tested for over a few hours--i'm 95% sure the code is not the problem. If my template list is bad, then that could be the problem
Quote:Original post by Toonkides
If my template list is bad, then that could be the problem
Is is a homebrewed list class or the standard C++ list class?
Calling _CrtDumpMemoryLeaks right before your program exits can be very useful when tracking down memory leaks. It will tell you what blocks of memory haven't been deleted yet, and what file they were allocated in. Look it up in your C++ library documentation.
Author
homebrewed template, from an ADT list in a book, thought it looked right when i did it, but now i have doubts
Author
unless the ADT was written wrong, I don't see where the problem is.
//-------------------------------------------------------------// Header for cList.h// ADT List - Pointer based implementation -- TEMPLATE VERSION//-------------------------------------------------------------#ifndef __CLIST_H__#define __CLIST_H__template <class T> struct listNode;template <class T> class cList{public: cList(); // constructor cList(const cList<T>& L); // copy constructor virtual ~cList(); // destructor void createList(); // creates an empty list void destroyList(); // destroys the list void copyList(const cList<T> &L); // copys a list bool isEmpty() const; // returns true if list is empty int getLength() const; // returns length of the list void insert(int position,T newItem,bool &success); // inserts item from position x in list void replace(int position,T newItem,bool &success); // replace item from list at position x with new item void remove(int position,bool &success); // removes item from position x in list void retrieve(int position,T &dataItem,bool &success); // retrives an item from position x in list private: int listLength; // length of the list listNode<T> *head; // the pointer to the head of the list listNode<T> *find(int position) const; // returns pointer to position in list};#include "cList.cpp"#endif//-----------------------------------------------------------// Implementation for cList.h//-----------------------------------------------------------#include<stddef.h> // for NULL#include<assert.h> // for asserttemplate <class T>struct listNode // node structure{ T item; // current item of the list listNode<T> *next; // pointer to next node in list listNode<T> *previous; // pointer to previous node in list};template <class T>cList<T>::cList(){ createList(); // create an empty list}template <class T>cList<T>::cList(const cList &L){ copyList(L) ;}template <class T>cList<T>::~cList(){ destroyList(); // destroys the list}template <class T>void cList<T>::createList() // creates an empty list{ head=new listNode<T>; head->next=NULL; head->previous=NULL; listLength=0;}template <class T>void cList<T>::destroyList() // destroys the list{ bool success; while(!isEmpty()) remove(1,success);}template <class T>void cList<T>::copyList(const cList &L) // copies the list{ if(L.head==NULL) // list to copy is empty head=NULL; else { // copy first node head = new listNode<T>; assert(head!=NULL); // check allocation head->item=L.head->item; //copy rest of the list listNode<T> *newPtr=head; // create pointer and set to head for(listNode<T> *origPtr=L.head->next;origPtr!=NULL;origPtr=origPtr->next) { newPtr->next=new listNode<T>; // create new node assert(newPtr->next!=NULL); // check allocation newPtr=newPtr->next; // go to next node newPtr->item=origPtr->item; // copy item } newPtr->next=NULL; } listLength = L.getLength() ;}template <class T>bool cList<T>::isEmpty() const // returns true if list is empty{ return bool(listLength==0);}template <class T>int cList<T>::getLength() const // returns length of the list{ return listLength;}template <class T>listNode<T>* cList<T>::find(int position) const{ if((position<1)||(position>getLength())) return NULL; else { listNode<T> *cur=head; for(int i=1;i<position;i++) cur=cur->next; return cur; }}template <class T>void cList<T>::insert(int position,T newItem,bool &success) // inserts item from position x in list{ listNode<T> *prev; listNode<T> *last; listNode<T> *newPtr; int newLength=getLength()+1; success=bool(position>0&&position<=newLength); if(success) { // create a new node and place item in it newPtr=new listNode<T>; success=bool(newPtr!=NULL); if(success) { listLength=newLength; newPtr->item=newItem; // attach new node to list if(position==1) { newPtr->previous=NULL; newPtr->next=head; if(getLength()>1) // if the current list is greater than one newPtr->next->previous=newPtr; head=newPtr; } else if(position==getLength()||position==getLength()+1) // if we are at the end of the list { newPtr->next=NULL; last=find(getLength()-1); newPtr->previous=last; last->next=newPtr; } else { prev=find(position-1); // insert new node after node // to which prev points newPtr->next=prev->next; newPtr->previous=prev; newPtr->next->previous=newPtr; prev->next=newPtr; } } }}template <class T>void cList<T>::replace(int position,T newItem,bool &success){ listNode<T> *newPtr; success=bool(position>0&&position<=getLength()); if(success) { newPtr=find(position); newPtr->item=newItem; }}template <class T>void cList<T>::remove(int position,bool &success){ listNode<T> *cur; listNode<T> *prev; success=bool(position>0&&position<=getLength()); if(success) { listLength--; if(position==1) { cur=head; head=head->next; if(head!=NULL) head->previous=NULL; } else { prev=find(position-1); cur=prev->next; prev->next=cur->next; if(position-1<getLength()) cur->next->previous=prev; } } cur->next=NULL; cur->previous=NULL; delete cur;}template <class T>void cList<T>::retrieve(int position,T &dataItem,bool &success){ listNode<T> *printPtr; success=bool(position>0&&position<=getLength()); if(success) { printPtr=find(position); dataItem=printPtr->item; }}Quote:Original post by Toonkides
homebrewed template, from an ADT list in a book, thought it looked right when i did it, but now i have doubts
use the standard library list, trust us its better than what you've got there, take alook here
Quote:Original post by snk_kid
use the standard library list, trust us its better than what you've got there, take alook here
Not the best advice, he should be able to get a linked-list working. If he just wanted more features, then sure.
Toonkides: just from a quick glance....
1) Why does an empty list contain a node? It looks like this has lead to several inconsitencies in your code.
2) 1-based indexing is odd in C, that could lead to mistakes if your not careful.
3) All the special cases you have for the head/tail of the list indicate that you need to rethink the design.
4) createList() will leak anything currently in the list
5) destroyList() will not destroy the head node created in createList() (or copyList() for that matter), since on creation the list contains a node when listLength==0
6) If your list is storing pointers replace() and remove() could leak memory.
7) A whole lot of bad stuff.... [sad]
It's probably worth you taking a look at a linked-list tutorial.
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