链表中倒数第k个节点

public class Reverse{
	static class LNode{
		int data;
		LNode next;
		public LNode(int data){
			this.data = data;
		}
	}
	LNode head;
	LNode current;
	public void add(int data){
		if(head == null){
			head = new LNode(data);
			current = head;
		}else{
		    current.next = new LNode(data);
			current = current.next;
		}
	}
	public void print(LNode node){
		LNode temp = node;
		while(temp!=null){
			System.out.println(temp.data);
			temp = temp.next;
		}
	}
	public LNode KNode(LNode head,int k){
	    LNode before = head;
	    LNode behind = head;
	    if(head == null || k==0) return null;
	    for(int i=1;i<k;i++){
	        if(before.next != null){
	            before = before.next;
	        }else {
	            return null;
	        }
	    }
	    while(before.next!=null){
	        before = before.next;
	        behind = behind.next;
	    }
	    return behind;
	}
	public static void main(String[] args){
		
		Reverse r = new Reverse();
		for(int i=1;i<10;i++){
			r.add(i);
		}
		//r.print(r.head);
		//倒数di yi g倒数第一个jie dian
// 		LNode result = r.KNode(r.head,1);
// 		r.print(result);
		//倒数第0个节点
        // LNode result = r.KNode(r.head,0);
        // r.print(result);
        //dao shu倒数倒数第di倒数第第10ge jie dian个节点
        LNode result = r.KNode(r.head,10);
        r.print(result);
		
	}
}