如何實現一個高效的單向鏈表逆序輸出?

問題:如何實現一個高效的單向鏈表逆序輸出?
出題人:阿里巴巴出題專家:昀龍/阿里雲彈性人工智能負責人
參考答案:下面是其中一種寫法,也可以有不同的寫法,比如遞歸等。供參考。

typedef struct node{
    int           data;
    struct node*  next;
    node(int d):data(d), next(NULL){}
}node;

void reverse(node* head)
{
    if(head == NULL){
        return;
    }

    node* pleft = NULL;
    node* pcurrent = head;
    node* pright = head->next;

    while(pright){
        pcurrent->next = pleft;
        node *ptemp = pright->next;
        pright->next = pcurrent;
        pleft = pcurrent;
        pcurrent = pright;
        pright = ptemp;
    }

    while(pcurrent != NULL){
        cout<< pcurrent->data << "\t";
        pcurrent = pcurrent->next;
    }
}
class Solution<T> {

    public void reverse(ListNode<T> head) {
       if (head == null || head.next == null) {
           return ;
       }
       ListNode<T> currentNode = head;
       Stack<ListNode<T>> stack = new Stack<>();
       while (currentNode != null) {
           stack.push(currentNode);
           ListNode<T> tempNode = currentNode.next;
           currentNode.next = null; // 斷開連接
           currentNode = tempNode;
       }

       head = stack.pop();
       currentNode = head;

       while (!stack.isEmpty()) {
           currentNode.next = stack.pop();
           currentNode = currentNode.next;
       }
    }
}

class ListNode<T>{
    T val;
    public ListNode(T val) {
        this.val = val;
    }
    ListNode<T> next;
}
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