单链表是一种顺序存取的结构，为找第 i 个数据元素，必须先找到第 i-1 个数据元素。因此，查找第 i 个数据元素的基本操作为：移动指针，比较 j 和 i -Linked list structure is a sequential access for the data elements to find the first i must first find the first i-1 data elements. Therefore, the first i find the basic operation of data elements are: move the pointer, compare j and i