Leetcode/java/206.reverse-linked-list.java at master · widmonstertony/Leetcode · GitHub

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/*
 * @lc app=leetcode id=206 lang=java
 *
 * [206] Reverse Linked List
 */

// @lc code=start
/**
 * 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) {
        ListNode currNode = head, preNode = null, nextNode;
        while (currNode != null) {
            nextNode = currNode.next;
            currNode.next = preNode;
            preNode = currNode;
            currNode = nextNode;
        }
        return preNode;
    }
}
// @lc code=end