30 lines
547 B
Java
30 lines
547 B
Java
package 链表;
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public class _206_反转链表 {
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public ListNode reverseList(ListNode head) {
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if (head == null || head.next == null) return head;
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ListNode newHead = reverseList(head.next);
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head.next.next = head;
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head.next = null;
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return newHead;
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}
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public ListNode reverseList2(ListNode head) {
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if (head == null || head.next == null) return head;
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ListNode newHead = null;
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while (head != null) {
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ListNode tmp = head.next;
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head.next = newHead;
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newHead = head;
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head = tmp;
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}
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return newHead;
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}
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}
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