/**
 * Definition of ListNode
 * class ListNode {
 * public:
 *     int val;
 *     ListNode *next;
 *     ListNode(int val) {
 *         this->val = val;
 *         this->next = NULL;
 *     }
 * }
 */
class Solution {
public:
    /**
     * @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
        ListNode *node,*dummy=new ListNode(0);
        dummy->next=head;
        head=dummy;
        node=head;
        int i,LEN=0;   
        while(node->next!=NULL)
        {
            LEN++;
            node=node->next;
        }
        if(n==1)
        {
            for(i=1;I<LEN+1-n;i++)
            {
                head=head->next;
            }
            head->next=NULL;
        }
        else
        {
            for(i=1;I<=LEN+1-n;i++)
            {
                    head=head->next;
            }
            *head=*(head->next);
        }
        return dummy->next;
    }
};