Thread: delete function does not work properly...

Code:

struct lista* del(struct lista* p, char* path1) {
       char model[MAX2];
       int len;
       char ch;
       
       printf("Type model.\n");
       scanf("%s", model);
       puts("\n");
       struct lista* t = p;
       if((strcmp(p->l.model, model)) == 0) {
           t = p->next;
           free(p);
           return t;
         }
       while((t->next) != NULL) {
        if((strcmp(t->l.model, model)) == 0) {
         struct lista* e = t->next;
         t->next = e->next;
         free(e);
         break;
        }
       t = t->next;
       }
return p;
}

Hello, this function should delete each element in the list which is the same as this one typed by user. There are no errors, but function doesnt work.
Can you please help me?

EDIT:// It deletes something, but not this element which should.

EDIT2// the function should delete the items which are equal to selected by user.
it deletes only one element...

I corrected this code to be similiar to previous:

Code:

struct lista* del(struct lista* p, char* path1) {
       int year;
       printf("Type year.\n");
       scanf("%d", &year);
       puts("\n");
       struct lista* t = p;
       if(p->l.year == year) {
           t = p->next;
           free(p);
           return t;
         }
       while((t->next) != NULL) {
        if(t->next->l.year == year) {
         struct lista* e = t->next;
         t->next = e->next;
         free(e);
         break;
        }
       t = t->next;
       }
return p;
}

It should delete an item from the list, when its equal to value served by user.
It delete a one item, but others are intact. :/

Originally Posted by tabstop

Then don't break out of the loop in the middle.

When I delete break from the loop, the function causes the whole program while deleting items is crashing.

Well, anyway, tabstop isn't wrong. It might not be as simple as removing the break statement, though.

It's much neater if you try to do this in a big loop. You will need a pointer to the current node, a next pointer, and a prev pointer. The reason is since next and prev change all the time, it is easiest just to save them, so you know where you are in the list. Then you loop over the list with respect to the current node. The idea is to move next and prev normally if the node DOES NOT match delete criteria -- this means progressing as next = current->next and prev = current by the end of the loop.

When the current node DOES get deleted, you need to
remove it from the list:
if (current == list) list = next; /* removing head */
if (prev != NULL) prev->next = next; /* removing other node */
delete the node:
free(current);