P14393 [GeeksforGeeks] Reverse a linked list
普及-
题目描述

Given a linked list of N nodes. The task is to reverse this list.
Example 1:
Input:
LinkedList: 1->2->3->4->5->6
Output: 6 5 4 3 2 1
Explanation: After reversing the list,
elements are 6->5->4->3->2->1.
Example 2:
Input:
LinkedList: 2->7->8->9->10
Output: 10 9 8 7 2
Explanation: After reversing the list,
elements are 10->9->8->7->2.
Your Task:
The task is to complete the function reverseList() with head reference as the only argument and should return new head after reversing the list.
Expected Time Complexity: O(N).
Expected Auxiliary Space: O(1).
Constraints:
1 <= N <= 10^{4}

输入格式

见题面

输出格式

见题面

样例输入
LinkedList:1->2->3->4->5->6
样例输出
6 5 4 3 2 1