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/**
* Definition for ListNode.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int val) {
* this.val = val;
* this.next = null;
* }
* }
*/
public class Solution {
/**
* @param head: The first node of linked list.
* @param n: An integer.
* @return: The head of linked list.
*/
ListNode removeNthFromEnd(ListNode head, int n) {
// write your code here
//count size of list
if(n == 0 && head ==null){
return null;
}
if(n == 0){
return head;
}
//compute list length
int len = 0;
ListNode node = head;
while(node != null){
len++;
node = node.next;
}
//n==len，删除head
if (n==len){
return head.next;
}
//len>n
int count = 1;
ListNode node1 = head;
while (count != len-n){
node1 = node1.next;
count++;
}
node1.next = node1.next.next;
return head;
}
}
