Question

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode swapPairs(ListNode head) {
        if (head == null|| head.next == null) return head;
        ListNode curr = head;//current node in list we are looking at
        ListNode retList = new ListNode(0);//new linked list to return
        ListNode newHead = retList;//reference to head of the list
        while(curr.next != null); {//while there is another point in the original list
            retList.val = curr.next.val;//the value in the return list = next value in original lis
            retList.next = new ListNode(curr.val);//opposite of last line+creates another node in return list
            if(curr.next.next == null) {//if there is another node after the next one
                curr = curr.next;//if there isnt then the while loop wont go
            }
            else {
                retList.next.next = new ListNode(0);//creates a new node 2 nodes ahead
                retList = retList.next.next;//goes to that node
                curr = curr.next.next;//jumps 2 nodes in the original list
            }
        }
        return newHead;//returns head to the list we are returning
    }
}

我真的无法弄清楚为什么这不起作用，while循环应该结束。提示是将列表中的每个节点与列表中的每个下一个节点交换 1,2,3,4变为2,1,4,3。它在leetcode https://leetcode.com/problems/swap-nodes-in-pairs/description/上每次我运行我的代码时，它只会给我一个超出时间的错误。

Answer 1

你的解决方案是正确的，但你的时间结束了。

链表中的交换节点溢出java

1 个答案: