链表反向不起作用……？

Question

I know it is a minute code. I can't understand why my linked list reversal is not working. Can some one help fix me my reverse method in the below code.

//Reverse a single linked list
public Node reverse()
{
    return reverse(root);
}
private Node reverse(Node node)
{
        Node previous = null;  
        Node current = node;  
        Node forward;  

        while (current != null) 
    {  
            forward = current.next;  
            current.next = previous;  
            previous = current;  
            current = forward;  
        }  
    return previous;  
}

Any input on this would be helpful

Thanks !!!

Answer 1

Assuming homework...

Write simple tests: list of 0 items, list of 1 items, list of 2 items, list of 10 items. Than make sure each of them work - will narrow down error and learn to write unit tests.

Answer 2

您确定使用返回值的reverse（）而不是root进行迭代吗？

Answer 3

I'm pretty sure it should be

return root = reverse(root);

(Your reverse logic is correct, but if the root is still pointing at the old root of the list, you will end up with a 1-element linked list.)