19. Remove Nth Node From End of List
难度:Medium
刷题内容
原题连接
- https://leetcode.com/problems/remove-nth-node-from-end-of-list/
内容描述
Given a linked list, remove the n-th node from the end of list and return its head.
Example:
Given linked list: 1->2->3->4->5, and n = 2.
After removing the second node from the end, the linked list becomes 1->2->3->5.
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/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* removeNthFromEnd(ListNode* head, int n) {
ListNode* current = head;
int num = 0;
while(current)
{
num++;
current = current ->next;
}
ListNode* n1 = new ListNode(0);
n1 ->next = head;
current = n1;
num -= n;
while(num)
{
num--;
current = current ->next;
}
ListNode* temp = current ->next;
current ->next = temp ->next;
return n1 ->next;
}
};
