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) {
        if(head == null) {
            return head;
        }
        ListNode prev = null;
        ListNode cur = head;
        ListNode temp = null;
        while(cur != null) {
            temp = cur.next;
            cur.next = prev;
            prev = cur;
            cur = temp;
        }
        return prev;
    }
}