Single LinkList 单向串行链结

[洛爾大嬸]

各位高手们好，小妹正在自修串炼连结，遇到以下问题
以下是程序代码:

struct student {
char name[20];
int score;
struct student *next;
}
struct student *ptr,*head,*current,*prev;

void insert_func(void){
ptr = (struct student *)malloc(sizeof(struct student));
ptr->name =(char *)”John”;
ptr->score = (int *) 85;

prev = head;
current = head->next;
while((current != NULL) && (current->score > ptr->score) ){
prev = currect;
current = current->next;
}
ptr->next = current;
prev->next = ptr;
}

以上是串炼连结的程序代码，它的目的是要写一个新增node并排序的函数。
我想请教 insert_func()中的程序代码，指标 prev = head 之后的部分看不懂，想求大神解释。

[赵4老师]

数据结构对单链表进行数据排序 http://bbs.csdn.net/topics/392201633