包括字符串反转， 链表反转， 判断两个数组中是否存在相同的数字， 判断链表是否存在环， 找出单向链表的中间结点， 如何判断一棵二叉树是否是平衡二叉树， strstr()的简单实现，,Including the string reversal, list reversal, to determine the existence of two different array of figures to determine the existence of ring list, find the middle of a one-way linked list nodes, how to determine whether it is a balanced binary tree Binary Tree, strstr () to achieve a simple,