[JS]链表倒数第k个节点
链表中倒数第k个结点
http://www.nowcoder.com/questionTerminal/529d3ae5a407492994ad2a246518148a
常规解法，快指针向前遍历k个
function FindKthToTail(head, k)
{
// write code here
let fast = head
let i=0
for(;i<k&&fast;i++){
fast = fast.next
}
if(!fast&&i<k){
return //k比链表的长度还大
}
while(fast){
head = head.next
fast = fast.next
}
return head
}
