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Implementing Multi-Linked List

quartaela (3)
hi there i am working on a project with implement a multi-linked list. in this list, nodes have a student's name,last name,birthday,address vs. i thought that i made it but i suppose i am implementing two separate linked lists, not a multi linked list which have 2 different header ( list->fn_head and list->ln_head ) and i recognize this problem when i delete a student by his name it deletes the node, but when i check this student's last name it says "this students exist". i appreciated if you can help me.

here are my structures

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typedef struct node {

    int birth_date;
    int zipcode;
    int phone_num;
    char first_name[50];
    char last_name[50];
    char city[50];
    char address[50];
    char email_addr[50];

    struct node* fn_next;
    struct node* fn_pre;
    struct node* ln_next;
    struct node* ln_pre;
    struct node* birdat_next;
    struct node* birdat_pre;

} NODE;

typedef struct {

    int fn_count;
    int ln_count;

    NODE* fn_head;
    NODE* ln_head;
    
    NODE* fn_tail;
    NODE* ln_tail;

}LIST;


and my adding functions by name and surname;

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void add_fn_Node(LIST* list, NODE* pnew_stu) {

    NODE* temp = list->fn_head;

    if( list->fn_head == NULL ) {

            pnew_stu->fn_next = list->fn_head;
            pnew_stu->fn_pre = list->fn_head;


            list->fn_head = pnew_stu;

            list->fn_count = 1;

            return;

        }

        else {

            temp = list->fn_head;

            if ( (strcmp( pnew_stu->first_name, temp->first_name )) <= 0 ) { // Condition for add before the first node

                pnew_stu->fn_next = temp;
                pnew_stu->fn_pre = temp->fn_pre;
                temp->fn_pre = pnew_stu;

                list->fn_head = pnew_stu;

                list->fn_count++;

                return;

            }

            else {
                
                 while ( temp->fn_next != NULL ) { // Condition for add middle

                        if ( (strcmp( pnew_stu->first_name, temp->first_name ) >= 0 ) && (strcmp( pnew_stu->first_name, temp->fn_next->first_name) < 0)) {

                        pnew_stu->fn_next = temp->fn_next;
                        pnew_stu->fn_pre = temp;
                        temp->fn_next->fn_pre = pnew_stu;
                        temp->fn_next = pnew_stu;

                        list->fn_count++;

                        return;
                    }

                        temp = temp->fn_next;

                    }

                if ( temp->fn_next == NULL ) { // Condition for add to end

                    temp->fn_next = pnew_stu;
                    pnew_stu->fn_pre = temp;
                    pnew_stu->fn_next = NULL;

                    list->fn_tail = pnew_stu;

                    list->fn_count++;

                    return;

                }
            }

        }
}

void add_ln_Node(LIST* list, NODE* pnew_stu) {

    NODE* temp = list->ln_head;

    if( list->ln_head == NULL ) {

            pnew_stu->ln_next = list->ln_head;
            pnew_stu->ln_pre = list->ln_head;


            list->ln_head = pnew_stu;

            list->ln_count = 1;

            return;

        }

        else {

            temp = list->ln_head;

            if ( (strcmp( pnew_stu->last_name, temp->last_name )) <= 0 ) { // Condition for add before the first node

                pnew_stu->ln_next = temp;
                pnew_stu->ln_pre = temp->ln_pre;
                temp->ln_pre = pnew_stu;

                list->ln_head = pnew_stu;

                list->ln_count++;

                return;

            }

            else {


                 while ( temp->ln_next != NULL ) { //Condition for add middle

                        if ( (strcmp( pnew_stu->last_name, temp->last_name ) >= 0 ) && (strcmp( pnew_stu->last_name, temp->ln_next->last_name) < 0)) {

                        pnew_stu->ln_next = temp->ln_next;
                        pnew_stu->ln_pre = temp;
                        temp->ln_next->ln_pre = pnew_stu;
                        temp->ln_next = pnew_stu;
                        
                        list->ln_count++;

                        return;
                    }

                        temp = temp->ln_next;

                    }

                if ( temp->ln_next == NULL ) { // Condition for add to end

                    temp->ln_next = pnew_stu;
                    pnew_stu->ln_pre = temp;
                    pnew_stu->ln_next = NULL;

                    list->ln_tail = pnew_stu;

                    list->ln_count++;

                    return;

                }
            }

        }
}


and this is the block where program read the text file line by line and call for adding operation

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while ( !feof(myfile) ) {

        NODE* pnew_stu;

        if( !(pnew_stu = (NODE*) malloc(sizeof(NODE))) ) {

            printf("ERROR NOT ENOUGH MEMORY!!!\n");
            exit(100);
        }

        fscanf(myfile,"%s", &(pnew_stu->first_name) );
        fscanf(myfile,"%s", &(pnew_stu->last_name) );
        fscanf(myfile,"%s", &(pnew_stu->email_addr) );
        fscanf(myfile,"%d", &(pnew_stu->phone_num) );
        fscanf(myfile,"%s", &(pnew_stu->address) );
        fscanf(myfile,"%s", &(pnew_stu->city) );
        fscanf(myfile,"%d", &(pnew_stu->zipcode) );

        add_fn_Node(list,pnew_stu);
        add_ln_Node(list,pnew_stu);

}
}
kfmfe04 (788)
for a long program like this, you need to post all your code so we can just drop it into the compiler and run it through a debugger

without all the code, we have to eyeball the code and run all these lines in our heads, which is not very pleasant

you also need to include a representative chunk of a data file which would cause the problem that you are describing
Last edited on
quartaela (3)
well mate i have nearly 10 header files. but if you want to see all codes i can upload my data so you can download it_?.
kfmfe04 (788)
sry not enough time to do it

to avoid issues like this in the future, it helps to unit-test your code - write a test, write new code to pass the test, write a new test - without unit-tests, it will be difficult to write reliable software beyond your 10 header files

since it's a little late for that, you need to user a debugger and step through your code
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