import?java.util.Scanner;

//命令錯誤異常
class?CommandException?extends?Exception
{
	CommandException(String?mis)
	{
		super(mis);
	}
}
//圖書不存在異常
class?NotExistException?extends?Exception
{
	NotExistException(String?mis)
	{
		super(mis);
	}
}

class?Books
{
	private?String[]?bookName=new?String[]{"論語","高數","數據結構","JAVA編程思想","囚徒健身"};
	//按書名查找
	public?String?nameSearch(String?name)?throws?NotExistException
	{
		for(String?str:bookName)
		{
			if(str.equals(name))
				return?str;
		}
		throw?new?NotExistException("圖書不存在!");
	}
	//按ID查找
	public?String?idSearch(int?id)?throws?NotExistException
	{
		if(id>bookName.length||id<=0)
			throw?new?NotExistException("圖書不存在!");
		return?bookName[id-1];
	}
	//運行程序
	public?void?search()?throws?CommandException,NotExistException
	{
		Scanner?input=new?Scanner(System.in);
		System.out.println("輸入命令:1-按照名稱查找圖書;2-按照序號查找圖書");
		int?n=input.nextInt();
		switch(n)
		{
			case?1:
			System.out.println("輸入圖書名稱:");
			System.out.println("book:"+nameSearch(input.next()));
			break;
			case?2:
			System.out.println("輸入圖書序號:");
			System.out.println("book:"+idSearch(input.nextInt()));
			break;
			default:
			throw?new?CommandException("命令輸入錯誤!請根據提示輸入數字命令!");
		}
	}
}


public?class?Library
{
	public?static?void?main(String[]?args)?//throws?CommandException,NotExistException
	{
		Books?b=new?Books();
		while(true)
		{
			try
			{
				b.search();
			}
			catch(NotExistException?e)
			{
				System.out.println(e.getMessage());
				continue;
			}
			catch(CommandException?e)
			{
				System.out.println(e.getMessage());
				continue;
			}
			catch(Exception?e)
			{
				System.out.println("命令輸入錯誤!請根據提示輸入數字命令!");
				continue;
			}
			break;
		}
	}
}