algorithm - 关于反向链表的问题(leetcode 206)

Question

我知道我的代码完全错误，但我不知道我哪里做错了，
谁能指出并解释我做错了什么？

public ListNode reverseList(ListNode head) {
    if (head == null) {
        return head;
    }
    
    ListNode prev = null;
    ListNode current = head;
    ListNode nextNode = head.next;
    
    while (nextNode != null) {
        prev = current;
        current = nextNode;
        current.next = prev;
        nextNode = nextNode.next;
        System.out.println(nextNode.val);
    }
    
    return current;
}

Answer 1

变化:

head.next = null;//使列表的末尾为空

current.next = 上一个；//current 是对节点的引用，因此对它的更改也会更改引用 nextNode 的节点

public ListNode reverseList(ListNode head) {
     if (head == null) {
         return head;
     }

     ListNode prev = null;
     ListNode current = head;
     ListNode nextNode = head.next;
     head.next = null;   // to make the end of the list as null

     while (nextNode != null) {
         prev = current;
         current = nextNode;
         nextNode = nextNode.next;   // first get next node, before ...
         current.next = prev;        // ... overwriting it here
         // System.out.println(nextNode.val);
     }

     return current;
 }