c - 删除链接列表中的项目 - 程序无法运行

Question

我的程序中有这个函数，可以删除链接列表上的特定值，例如:

Value to be deleted: 8

Linked List: 2 -> 9 -> 8 -> 3 -> 5 -> X

List after removal of value: 2 -> 9 -> 3 -> 5 -> X

问题是，它没有按预期工作。下面是我的函数的代码:

void removeValue(DLList L, int value){
assert (L != NULL);
DLListNodeP curr = L->curr;
while (curr != NULL){
    if (curr->value == value){
        if (L->first == L->last){   // If there is only one item in the list
            L->curr = NULL;
            L->first = NULL;
            L->last = NULL;
            L->nitems = 0;
        }

        else if (L->curr->next == NULL){    // If current item is the last item on the list
            L->curr->prev->next = NULL;
            L->last = L->curr->prev;
            free (L->curr);
            L->last->next = NULL;
            L->curr = L->last;
            L->nitems--;
        }

        else if (L->curr->prev == NULL){ // If current item is the first item on the list
            L->curr = L->curr->next;
            free (L->curr->prev);
            L->curr->prev = NULL;
            L->first = L->curr;
            L->nitems--;
        }

        else {
            DLListNodeP next = L->curr->next;
            L->curr = NULL;
            L->curr = next;
            L->curr->prev->next = L->curr->next;
            L->curr->next->prev = L->curr->prev;
            L->nitems--;
        }

        L->curr = L->curr->next;
    }
    else {
        L->curr = L->curr->next;
    }
}

return; }

我尝试过修改代码，一次修改一部分，但仍然无法使其工作；我几乎尝试了一切。我可以做些什么来使这段代码正常工作吗？谢谢

Answer 1

DLListNodeP prev = L->curr, next = L->curr->next; // Check if curr exists
if (prev->value == value) {
   L->curr = next;
   return;
}

while (next != NULL){
   if (next->value == value) {
      prev->next = next->next;
      break;
   }
   prev = next;
   next = next->next;
}