Recursion Function(재귀함수) : 자기 자신을 재참조, 종료 조건으로 종료 시점을 제어한다.
leetcode : 206. Reverse Linked List
- 조건
- The number of nodes in the list is the range [0, 5000].
- -5000 <= Node.val <= 5000
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/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode() {}
* ListNode(int val) { this.val = val; }
* ListNode(int val, ListNode next) { this.val = val; this.next = next; }
* }
*/
class Solution {
public ListNode reverseList(ListNode head) {
if (head == null || head.next == null) {
return head;
}
ListNode nextNode = head.next;
head.next = null;
ListNode current = reverseList(nextNode);
nextNode.next = head;
return current;
}
}