19-Remove Nth Node From End of List

100-Same Tree | Links:

题意

Given the head of a linked list, remove the nth node from the end of the list and return its head. Follow up: Could you do this in one pass?

Example 1:
Input: head = [1,2,3,4,5], n = 2
Output: [1,2,3,5]

Example 2:
Input: head = [1], n = 1
Output: []

思路

• 链表删除
• 快慢针

分析:

• Time: O(n)
• Space: O(1)