题解 | #链表中倒数最后k个结点#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution {
    /**
     * 思路: 倒数第K个节点在length-K处.
     *
     * 
     * @param pHead ListNode类 
     * @param k int整型 
     * @return ListNode类
     */
    public ListNode FindKthToTail (ListNode pHead, int k) {
        // write code here
        if(k==0){
            return null;
        }
        int i=1;
        ListNode knode = null;
        ListNode first = pHead;
        while(pHead!=null){
            if(i==k){
                knode=first;
            }
            if(i>k){
                knode=knode.next;
            }
            i++;
            pHead=pHead.next;
        }
        return knode;
    }
}