README.md

@@ -354,7 +354,58 @@ Reader* LendBook(Reader* reader1, Book* book1)
 函数原形：void returnBook(Reader* reader, Book* book);
 功能：接受两个形参：读者链表地址和图书链表地址，用读者的编号进行匹配，找到该读者后，用图书的编号进行匹配，进行还书，否则返回
 ```
-
+void returnBook(Reader* reader1, Book* book1)
+{
+	Reader* reader = reader1;
+	Book* book = book1;
+	printf("请输入读者的id:");
+	int id;
+	scanf("%d", &id);
+	getchar();
+ 
+	if (reader != NULL)
+	{
+		while (reader != NULL)
+		{
+			if (id == reader->iNum)
+			{
+				printf("请输入要还的书的编号:");
+				int id_book;
+				scanf("%d", &id_book);
+				getchar();
+				for (int i = 0; i < reader->iMax; i++)
+				{
+					if (reader->aiBookId[i] == id_book)
+					{
+						reader->aiBookId[i] = 0;
+						while (book)
+						{
+							if (id_book == book->iNum)
+							{
+								book->iAmount++;
+								printf("还书成功!\n");
+								printf("按任意键返回\n");
+								getchar();
+								return reader1;
+							}
+							book = book->next;
+						}
+					}
+				}
+				printf("没有找到该图书，检查图书的Id\n");
+ 
+				printf("按任意键返回\n");
+				getchar();
+				return reader1;
+			}
+			reader = reader->next;
+		}
+		printf("没有找到该读者，检查读者id是否输入有误\n");
+		printf("按任意键返回\n");
+		getchar();
+		return reader1;
+	}
+}
 
 
 ```
@@ -363,9 +414,35 @@ Reader* LendBook(Reader* reader1, Book* book1)
 1）函数原形: void save(Book* book);
 2) 功能：接受一个形参：book的链表地址，新建一个文件，将链表中的信息保存到硬盘中
 ```
-
-
-
+void save(Book* book1)
+{
+	FILE* fp;
+	Book* pCur = book1;
+	int iCount = 0;
+ 
+	if (pCur == NULL)
+	{
+		printf("\n没有学生记录!\n");
+		return;
+	}
+ 
+	if ((fp = fopen("book.txt", "wb")) == NULL)
+	{
+		printf("创建文件失败!\n");
+		getchar();
+		exit(1);
+	}
+	while (pCur)
+	{
+		fwrite(pCur, sizeof(Book), 1, fp);
+		pCur = pCur->next;
+		iCount++;
+	}
+	printf("\n");
+ 
+	printf("保存文件的数据数目为:%d\n", iCount);
+	fclose(fp);
+}
 ```
 
 ## C12:读取信息模块
@@ -373,6 +450,33 @@ Reader* LendBook(Reader* reader1, Book* book1)
 1）函数原形: Book* read1();
 2) 功能：打开一个文件，将文件中的信息读取到内存中，并返回一个Book类型的指针
 ```
+Book* read1()
+{
+	FILE* fp;
+	Book* pHead = NULL, * pTemp = NULL, * pCur = NULL;
+ 
+	if ((fp = fopen("book.txt", "r")) == NULL)
+	{
+		printf("\n文件打开失败!请检查文件名!\n");
+		exit(0);
+	}
+	pTemp = (Book*)malloc(sizeof(Book));
+	while (fread(pTemp, sizeof(Book), 1, fp))
+	{
+		if (!pHead)
+		{
+			pHead = pCur = pTemp;
+		}
+		else
+		{
+			pCur->next = pTemp;
+			pCur = pTemp;
+		}
+		pTemp = (Book*)malloc(sizeof(Book));
+	}
+	fclose(fp);
+	return pHead;
+}
 
 
 ```