题解 | #反转链表#

/*
public class ListNode {
    int val;
    ListNode next = null;

    ListNode(int val) {
        this.val = val;
    }
}*/
public class Solution {
    public ListNode ReverseList(ListNode head) {
        ListNode node = head;
        if(head == null) return null;
        head = head.next;
        node.next = null;
        // System.out.println(head);
        while (head != null) {
            ListNode temp = head;
            head = head.next;
            temp.next = node;
            node = temp;
            
            // System.out.println(node);

        }

        return node;
    }
}