can figure out what this function does..

its so complicated
i cant see the general way

Code:

---

Node* what2(Node *head){
        Node *temp, *prev, *next, *prevmax, *newhead;       
        while(head->next){
                prevmax = prev = next = NULL;
                for(temp=head; temp; temp=temp->next){
                        printf("%d ", temp->value);
                        next = temp -> next;
                        if((!prev || prev->value < temp->value) &&
(!next || temp->value > next->value)){
                                if(! prevmax )
                                        newhead = temp;
                                else
                                        prevmax->next= temp;
                                prevmax = temp;
                        }
                        if(prev && prev!=prevmax)
                                free(prev);
                        prev = temp;
                }
                prevmax -> next = NULL;
                head = newhead;
                putchar('\n');
        }
        return head;
}

---

It would appear to find the largest element in a singly-linked-link, and free the entire list except for that element. I would also add that this code smells, and I can't tell you for certain that it is bug free/works. If it does indeed free everything but the largest element, then I would have written it:

Code:

---

Node *reduce(Node *head)
{
        Node *largest = NULL, *i, *temp;
       
        // Find the max
        for(i = head; i; i->next)
        {
                largest = (largest && largest->value > i->value ? largest : i);
        }
       
        // Free everything but the max
        for(i = head; i;)
        {
                temp = i;
                i = i->next;
                if(temp != largest)
                {
                        free(temp);
                }
        }
       
        return largest;
}

---

About 15 lines less, much easier to read, and I can even tell you that it runs in O(N).