• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0
DishSoap

Pointer to Pointer Issue

4 posts in this topic

*EDIT* As Ardvajk pointed out, while printing I am using the variable 'used' which == elements in the map. I should be using the number of bins or buckets in my array. 

 

Hey everyone, I'm having some strange issues I was hoping someone could help with. Basically I am inserting into a HashSet at the same index in an array [0] in my case. And when I loop through to print all the elements in the set I get some strange output for the bucket at index [1] even though I believe it to be completely empty. Also, this is a homework assignment, so just some guidance and not an outright answer would be appreciated smile.png

 

I am building a HashSet where the map is basically a pointer to a pointer of nodes. Hopefully I'm not posing a wall of code here next, as that would be annoying. But I have to post quite a bit for you to see what's going on. The declaration looks as such:

Node** set      = nullptr;
...
Node (T v,  Node* n = nullptr) : value(v), next(n){} // Relevant constructor

In my constructor for the HashSet I initialize the set to such:

template<class T>
HashSet<T>::HashSet(int (*func)(const T& element), double load) : hash(func), load_factor(load) {
	set = new LN*[bins];
	for(int i = 0; i < bins; i++) set[i] = nullptr;
}

My insert statement looks like this:

template<class T>
int HashSet<T>::insert(const T& element) {
  //write code here
	if(!contains(element))
	{
		int index = hash_compress(element);
	        Node* temp = set[index];
		if(temp == nullptr)
		{
			temp = new LN(element);
			set[index] = temp;
		}
		else
		{
			Node* new_node = new LN(element, set[index]);
			set[index] = new_node;
		}
		maintain_load(++used);
	}
}

Ok, that's all I will post. As I don't want to post too much, but I am happy to give more code if needed. Basically in my test, you will have to trust that int index = 0 for two inserts. After the second insert, the item gets properly inserted into bucket 0 but basically fills bucket 1 with a ton of garbage. To be exact, when I go to print it out all of my environment variables and the alphabet print out, it's kind of funny looking smile.png

 

My print method basically looks like this:

for(int i = 0; i < bins; i++) // used to be i < used
	{
		Node* temp = set[i];
		std::cout << "[" << i << "]" << std::endl;
		std::cout << "{" << std::endl;
		while(temp != nullptr)
		{
			std::cout << temp->value << std::endl;
			temp = temp->next;
		}
		std::cout << "}" << std::endl;
	}
Edited by DishSoap
0

Share this post


Link to post
Share on other sites
Haha. I figured it out driving to school. Funny how a 10 minute break after staring at something for hourd makes you realize your mistaked. How can I delete this thread??
0

Share this post


Link to post
Share on other sites
You seen to be incrementinf your used variable upon any insert, the when printing, using it as a count of the hash entries. Two inserts with a hash of 0 will leave hash bucket 1 empty, but your print code thinks 0 and 1 are used hashes.

Hard to be sure viewing this on mobile but seems odd to me.
1

Share this post


Link to post
Share on other sites

Haha. I figured it out driving to school. Funny how a 10 minute break after staring at something for hourd makes you realize your mistaked. How can I delete this thread??


Don't delete, post your fix. Might be useful to someone in the future searching for a similar issue.
1

Share this post


Link to post
Share on other sites

That was exactly the issue. I will fix my post when I get home.

 

*EDIT*

Home now! I fixed it. Thank you.

Edited by DishSoap
0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0