针对带附加头结点的单链表，试编写下列函数。

（1）定位函数Locate:在单链表中寻找第i个结点。若找到，则函数返回第i个结点的地址；若找不到，则函数返回NULL。

（2）求最大值函数max：通过一趟遍历在单链表中确定值最大的结点。

（3）统计函数number：统计单链表中具有给定值x的所有元素。

（4）建立函数create：根据一维数组a[n]建立一个单链表，使单链表中各元素的次序与a[n]中各元素的次序相同，要求该程序的时间复杂性为O(n)。

-Singly linked list with additional head node, try to write the following function.

(1) orientation function Locate is: in a single linked list to find the i-th node. If found, the function returns the i-node address　if no, then the function returns NULL.

(2) the maximum function max: traversing through a trip to determine the value of the largest node in a singly linked list.

(3) The number of statistical functions: statistical singly linked list with all the elements of a given value of x.

(4) the establishment of the create function: one-dimensional array a [n] to establish a single linked list, singly linked list in the order of the elements a [n] is the order of the elements of the same requirements of the program s time complexity is O (n).