* function ListNode(x){
 *   this.val = x;
 *   this.next = null;
 * }
 */
/**
 * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
 *
 * 
 * @param pHead ListNode类 
 * @param k int整型 
 * @return ListNode类
 */
function FindKthToTail( pHead ,  k ) {
    // write code here
    let fast = pHead,slow = pHead;
    for(let i = 0;i < k;i++){
        if(fast){
            fast = fast.next;
        }else{
            return "";
        }
    }
    while(fast){
        fast = fast.next;
        slow = slow.next
    }
    return slow;
}
module.exports = {
    FindKthToTail : FindKthToTail
};

alt