Record Case Detail - VG101 FA2021 (Jigang) - JOJ

This function is in beta test. Please help improve it in the issues here.

Your answer may be identical to the JOJ answer in the first several lines.

However, you will still get Wrong Answer because the complete output may be longer and there might be errors in the future lines.

Please double check your code to solve this problem and try again.

Welcome to the library management system, please type your commands.
> Test1 added to the system.
> 1 Test1 on shelf
> The book ID already exists.
> 1 Test1 on shelf
> c1 added to the system.
> 1 c1
> The reader ID already exists.
> 1 c1
>  Exit the system!

Welcome to the library management system, please type your commands.
> Test1 added to the system.
> 1 Test1 on shelf
> The book ID already exists.
> 1 Test1 on shelf
> c1 added to the system.
> 1 c1
> The customer ID already exists.
> 1 c1
> Exit the system!