Data Structure in C Please help ADT's

**slim3883** · 05-30-2009

I started Data Structures and the professor doesnt know what he is doing. He took a project from another school and gave it to us. I know how to program in C but never worked with ADT and binding its completely new to me. I figured out the .h files which is easy but can not understand how to make my .c files work with his "test code". I am attaching the project in a pdf file if anyone could help i would greatly appreciate it. At least point me in the right direction I know the .h files attach to the main and then my .c files attach to the .h files I already made. Thank you anyone that can help.

**tabstop** · 05-31-2009

If you know that "the .h files attach to the main and then my .c files attach to the .h files" you know way more than the rest of us. I don't even know what that means, let alone that it's true.

In the attached document, your instructor appears to be using the word "binding" where I might use the word "(ordered) pair" -- he just means that the key and the value are associated together and shouldn't ever be split apart.

**ninety3gd** · 05-31-2009

Do you have a textbook or use other sources to help as well?

**slim3883** · 05-31-2009

Yes i have the text book it doesnt help. he has not discussed the project much just threw it at us. Even another student that I showed this project to that took the course last semester, but with a different professor, did not even know what it is asking for.

**laserlight** · 05-31-2009

Just to check: you have written the header file and implementation, but now the problem is that you do not know how to get your implementation to work with your instructor's sample tests?

If so, what do the sample tests consist of?

**slim3883** · 05-31-2009

We are supposed to use GCC compiler. I am new to Data Structures I am ok in C. I really dont even understand the implementation part of it.

**laserlight** · 05-31-2009

Originally Posted by slim3883

We are supposed to use GCC compiler. I am new to Data Structures I am ok in C. I really dont even understand the implementation part of it.

Okay, so you have not started at all?

What I would do is to define a structure. Reading the section of how to implement this data structure, it is clear that I would need a pointer so that I can do dynamic memory allocation. It is also clear that I need to keep track of the capacity (number of elements allocated) and the size (number of elements in use) so that I can expand the dynamic array when needed.

So, we are faced with a problem: what type should this pointer be? Looking at the requirements for Set_getValue(), we see that it returns a void*. Right, maybe we can use a pointer to void*. Next, in order to modify the set and to avoid unnecessary copying, we most likely should make Set_T a pointer type. Consequently, we might start by defining:

Code:

struct Set
{
    void **data;
    size_t capacity;
    size_t size;
};

typedef struct Set* Set_T;

From here, think of how you might implement Set_new(). Do not be afraid to modify the definition of the structure that I showed.

**slim3883** · 05-31-2009

ok So I posted the test code. This is what I had for Set_new()

Code:

Set_T set = malloc (sizeof(Set_T));
  return set;

I had the struct sort of like yours in my setInterface.h like this

Code:

  typedef struct {
     ItemType key;
     ItemType value;

  } Set_T;

because I thought that each struct would have a key and value so I know I might be wrong. I really appreciate this help though let me know if you see if what I am doing is wrong. Thanks

**laserlight** · 05-31-2009

Originally Posted by slim3883

because I thought that each struct would have a key and value so I know I might be wrong.

Be more confident. You have the right idea, but the problem is that you have defined a structure appropriate for a key/value pair, not a set (or rather, a map; the terminology used by the assignment is not accurate in that sense).

So, what you need to do is to have a dynamic array of key/value pairs.

Originally Posted by slim3883

This is what I had for Set_new()

That would be wrong. Set_new is supposed to initialise the set.

**slim3883** · 05-31-2009

I appreciate the help. I will keep working on it and see if I can figure it all out. If there are any other ideas you might have or things you think I might need to know please tell me. This project is very overwhelming for me

Thread: Data Structure in C Please help ADT's

Thread Tools

Search Thread

Display

Data Structure in C Please help ADT's

Similar Threads

pthread question how would I init this data structure?

Data structure implementation

can't insert data into my B-Tree class structure

Tab Controls - API

Dynamic Data Structure -- Which one is better?