Thread: Help guys with circluarly linked list

Code:

    struct p_item *newnode, *first=list;
     
    if (list==NULL){
         
        list=malloc(sizeof(*list));
        if (list == NULL) {
            fprintf(stderr, "Out of memory\n");
            exit(1);
        }
        list->p_letter=letter;
        strcpy(list->p_word, word);
        list->p_next=first;
        return first;
    }

Where in THE ABOVE code does first get set to a value that is valid (non NULL value) to return?

"First" is my first node in the list.

Your above code makes this a false statement.

Tim S.

"List" is my circularly linked list.
"First" is my first node in the list.

In what way does your meaning of "List" and "First" differ in meaning?

Why NOT just return "List"?

You NEED to decide what the code variables you are using means.

Looking at your code; changing the name of "List" to "Last" might make sense.

What is the function addnode() supposed to be returning?

How is mylist supposed to be updated?

Tim S.

Check this: circularly linked list . Why does it work for him and not for me? I took the code and modified the variable names, added the one about word and read it.

Mine keeps giving me error "Line 54 conflicting types for 'addnode''" and "Line 44 previous implicit declaration of 'addnode' was here".

I give you the modified code.

If I get it right mylist is updated by "mylist = addnode(mylist, letter, word);". But why conflicting types for addnode;

Code:

Lics()
{
    struct p_item *mylist = NULL;
    char letter;
    char word[SIZE];
    FILE *phonetics;
     
    i=0;
    phonetics=fopen("ICAO.phon", "r");
    if (phonetics == NULL){
        printf ("Error opening file\n");
        return;
    }
    else {
        while(!feof(phonetics)) {
            if (fscanf(phonetics, "%c\n", &letter) != NULL) {
                if (fscanf(phonetics, "%s\n", word) != NULL) {
                    printf("%c %s\n", letter, word);  
                    mylist = addnode(mylist, letter, word);              
                }
            }
        }
    }
    printf("\n\n");
    printlist(mylist);
     
    return;
}
  
struct p_item *addnode(struct p_item *list,char letter, char word[SIZE])
{
    struct p_item *newnode, *first=list;
    if (list==NULL){
        
        newnode=malloc(sizeof(*newnode));
        if (newnode == NULL) {
            fprintf(stderr, "Out of memory\n");
            exit(1);
        }
        newnode->p_letter=letter;
        strcpy(newnode->p_word, word);
        newnode->p_next=newnode;
        return newnode;
    }
     
    while (list->p_next != first){
        list = list->p_next;
        }
    newnode=malloc(sizeof(*newnode));    
    list->p_next = newnode;
    newnode->p_letter=letter;
    strcpy(newnode->p_word, word);
    newnode->p_next = first;
  
    return first;
}

He put his main after the functions; you need to write function prototypes as we stated long past in this thread or move your main after the functions.

Tim S.

PS: I feel I am not helping you since you seem to be NOT learning; so, I am going to sign off for now.

Originally Posted by stahta01

You need to use Function Prototypes and READ YOUR COMPILER warnings!

http://www.cprogramming.com/tutorial/c/lesson4.html
Tim S.

Originally Posted by lios1984

I promise I will study more and ask less.

Asking is NOT the problem; ignoring the answers is the problem.

FYI: Cheating on programming is like cutting off you hand because it hurts to write.

Tim S.