LeetCode 反转链表 迷南。 2022-09-11 06:27 94阅读 0赞 # 1 反转链表 # 给你单链表的头节点 head ,请你反转链表,并返回反转后的链表。 ![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16] 输入:head = [1,2,3,4,5] 输出:[5,4,3,2,1] ![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16 1] 输入:head = [1,2] 输出:[2,1] # 2 解题 # ## 2.1 迭代 ## public ListNode reverseList(ListNode head) { ListNode currentNode = head; ListNode preNode = null; while (currentNode != null) { ListNode tempNode = currentNode.next; currentNode.next = preNode; preNode = currentNode; currentNode = tempNode; } return preNode; } ![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16 2] ## 2.2 递归 ## public ListNode reverseList(ListNode head) { if (head == null || head.next == null) { return head; } ListNode restHead = head.next; ListNode reversedRest = reverseList(restHead); restHead.next = head; head.next = null; return reversedRest; } ![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_18_color_FFFFFF_t_70_g_se_x_16] [watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16]: /images/20220828/69bf049499594810ba6d8c91d5493125.png [watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16 1]: /images/20220828/ba45017147024db3abd9db2caf719ce1.png [watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_20_color_FFFFFF_t_70_g_se_x_16 2]: /images/20220828/1438603c0d1844888eb908cbcbd5c48a.png [watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5L2g5pC656eL5pyI5o-95pif5rKz5Li2_size_18_color_FFFFFF_t_70_g_se_x_16]: /images/20220828/e0349eabf04348f580fee1445c694260.png
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