考虑到图书信息和读者信息中都包含有不同类型的数据，故分别建立图书和读者两种类型的结构体；由于图书和读者的数量非固定，所以采用动态链式存储来实现。-Taking into account the information in the book information and readers are different types of data included, so the books and readers were established two types of structures