lintcode 466. 链表节点计数

466. 链表节点计数

计算链表中有多少个节点.

 

样例

给出 1->3->5, 返回 3.

 /**
  * Definition of ListNode
  * class ListNode {
  * public:
  *     int val;
  *     ListNode *next;
  *     ListNode(int val) {
  *         this->val = val;
  *         this->next = NULL;
  *     }
  * }
  */

 class Solution {
 public:
     /*
      * @param head: the first node of linked list.
      * @return: An integer
      */
     int countNodes(ListNode * head) {
         // write your code here
         int count = ;
         while (head->next) {
             count++;
             head = head->next;
         }
         return count;
     }
 };