代码解释，无法理解，需要详细解释

#include<stdio.h>
#include<string.h>
typedef struct Book{ //定义书籍信息
char ISBN[20];
char bookName[20];
double Price;
}Book;

typedef struct LNode{ //定义书籍节点
Book data;
struct LNode * next;
}LNode, *LinkList;

void InitList(LinkList list) //初始化链表
{
if (list->next == NULL)
{
return;
}
list->next = NULL;
}

LNode *GetNode(Book book)//生成一个节点
{
LNode * pGet = (LNode *)malloc(sizeof(LNode));
strcpy(pGet->data.bookName, book.bookName);
strcpy(pGet->data.ISBN, book.ISBN);
pGet->data.Price = book.Price;
pGet->next = NULL;
return pGet;
}

void InsertTailList(LinkList list, Book book)//尾插
{
LNode *pCur = list;
while ((pCur->next) != NULL)
{
pCur = pCur->next;
}
LNode *pGet = GetNode(book);
pCur->next = pGet;
}

LNode *nameFind(LinkList list, char *name) //书名查找
{
LNode *pCur = list->next;
while (strcmp(pCur->data.bookName, name))
{
pCur = pCur->next;
}
return pCur;
}

void Delete(LinkList list, int val) //删除第val本书籍
{
LNode* pCur = list;
int count = 1;
while (count != val)
{
pCur = pCur->next;
count++;
}
pCur->next = pCur->next->next;
}

int Getlength(LinkList list) //得到长度
{
int count = 0;
LNode* pCur = list->next;
while (pCur != NULL)
{
count++;
pCur = pCur->next;
}
return count;
}

void Modify(LinkList list, int val,Book book)//修改书籍
{
int tmp = 1;
LNode* pCur = list->next;
while (tmp != val)
{
pCur = pCur->next;
tmp++;
}
strcpy(pCur->data.ISBN, book.ISBN);
strcpy(pCur->data.bookName, book.bookName);
pCur->data.Price = book.Price;
}

void Show(LinkList list) //打印
{
LNode *pCur = list->next;
while (pCur != NULL)
{
printf("%s ", pCur->data.ISBN);
printf("%10s ", pCur->data.bookName);
printf("%6d ", pCur->data.Price);
printf("\n");
pCur = pCur->next;
}
printf("\n");
}
int main()
{
printf("=============================\n");
printf(" 图书管理系统\n");
printf(" 1、初始化系统\n");
printf(" 2、查看当前存放的书籍\n");
printf(" 3、向系统录入书籍\n");
printf(" 4、查找书籍\n");
printf(" 5、删除书籍\n");
printf(" 6、查看当前书籍总量\n");
printf(" 7、修改书籍信息\n");
printf(" 0、退出系统\n");
printf("\n");
printf("=============================\n");
int tmp;
int count = 1;
LNode list;
InitList(&list);
while (count){
printf("请输入你的操作\n");
scanf_s("%d", &tmp);
switch (tmp)
{
case 1:
{
InitList(&list);
printf("初始化完成！\n");
count = 1;
break;
}
case 2:
{
Show(&list);
count = 1;
break;
}
case 3:
{
int ret = 0;
printf("你想输入多少本书籍？");
scanf_s("%d", &ret);
for (int i = 0; i < ret; i++)
{
Book book;
printf("书籍的ISBN号：");
scanf("%s", book.ISBN);
printf("书名：");
scanf("%s", book.bookName);
printf("书籍价格：");
scanf_s("%d", &book.Price);
InsertTailList(&list, book);
printf("录入完成！\n");
}
count = 1;
break;
}
case 4:
{
char arr[10] = { NULL };
printf("请输入要查找书籍的书名：");
scanf("%s", arr);
printf("%s", nameFind(&list, arr)->data.ISBN);
printf("%10s ", nameFind(&list, arr)->data.bookName);
printf("%6d ", nameFind(&list, arr)->data.Price);
printf("\n");
break;
}
case 5:
{
int val = 0;
printf("请输入想删除第几本书！");
scanf_s("%d", &val);
Delete(&list, val);
printf("删除成功！");
count = 1;
break;
}
case 6:
{
printf("当前书库有%d本书籍！\n",Getlength(&list));
count = 1;
break;
}
case 7:
{
int val = 0;
Book book;
printf("请输入你想修改第几本书籍！");
scanf("%d", &val);
printf("书籍的ISBN号：");
scanf("%s", book.ISBN);
printf("书名：");
scanf("%s", book.bookName);
printf("书籍价格：");
scanf_s("%d", &book.Price);
Modify(&list, val,book);
printf("修改成功！");
count = 1;
break;
}
case 0:
{
printf("退出系统成功！\n");
count = 0;
}
default:
break;
}
}

}

望采纳，谢谢 就是一个简单的图书系统，控制台输出的，