标签：list lin turn this move ssi you ast example
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.
Note:
Given n will always be valid.
Follow up:
Could you do this in one pass?
AC code:
/**
* 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* demo = new ListNode(0);
demo->next = head;
ListNode* fast = demo;
ListNode* slow = demo;
for (int i = 0; i < n; ++i) {
fast = fast->next;
}
while (fast->next) {
slow = slow->next;
fast = fast->next;
}
slow->next = slow->next->next;
return demo->next;
}
};
Runtime: 8 ms, faster than 34.35% of C++ online submissions for Remove Nth Node From End of List.
step1: 1 -> 2 -> 3 -> 4 -> 5 demo: 0 -> 1 -> 2 -> 3 -> 4 -> 5 fast: / slow: / step2: 1 -> 2 -> 3 -> 4 -> 5 demo: 0 -> 1 -> 2 -> 3 -> 4 -> 5 fast: / slow: / step3: 1 -> 2 -> 3 -> 4 -> 5 demo: 0 -> 1 -> 2 -> 3 -> 4 -> 5 fast: / slow: / step4: 1 -> 2 -> 3 -> 4 -> 5 demo: 0 -> 1 -> 2 -> 3 -> 4 -> 5 fast: / slow: / step5: fast->next == null slow->next = slow->next->next; 1 -> 2 -> 3 -> 4 -> 5 demo: 0 -> 1 -> 2 -> 3 4 -> 5 fast: | /| slow: | | |_______|
19. Remove Nth Node From End of List
标签：list lin turn this move ssi you ast example
原文地址：https://www.cnblogs.com/ruruozhenhao/p/9741047.html
