輸入一個鏈表,輸出該鏈表中倒數第k個結點。(前後雙指針,指針之間相距爲K)
public class Solution {
public ListNode FindKthToTail(ListNode head,int k) { //5,{1,2,3,4,5}
ListNode p, q;
p = q = head;
int i = 0;
for (; p != null; i++) {
if (i >= k)
q = q.next;
p = p.next;
}
return i < k ? null : q;
}
}