建立一个类，用来保存图书馆图书卡片，存储书的书名、作者、出版日期、未借出的数量，统计库中图书的总量

我写了一个代码。。可是有错误，我又找不出，特请各位大侠帮帮忙。。以下是我的代码。
#include<iostream>
#include<string>
using namespace std;
class Library(){
public:
Library(char *bname,char *wname,char *bdata,int rnum,int tnum)
{
bookname=new char[strlen(bname)+1];
if(bookname!=NULL)strcpy(bookname,bname);
writername=new char[strlen(wname)+1];
if(writername!=NULL)strcpy(writername,wname);
bookdata=new char[strlen(bdata)+1];
if(bookdata!=NULL)strcpy(bdata,bookdata);
remainnumber=rnum;
totalnumber=tnum;
cout<<"构造函数L"<<endl;
}
void print()
{
cout<<"书名："<<bookname<<endl;
cout<<"作者："<<writername<<endl;
cout<<"出版日期："<<bookdate<<endl;
cout<<"未借出书籍的数量："<<remainnumber<<endl;
cout<<"图书总量："<<totalnumber<<endl;
}
~Library()
{cout<<"析构函数L"<<endl;}

char *bookname,*writername,*bookdate;
int remainnumber,totalnumber;

};
void main()
{
Library b("happy","张宏","2012/12/12",100,200);
b.print();
}

相关了解……