There are 3 blocks in the Hall, labeled as letters A to C. Each block has 4 floors, with 3 rooms on each floor. Print a series of strings in the format of "[Block][Floor number][Room number] to be...

There are 3 blocks in the Hall, labeled as letters A to C. Each block has 4 floors, with 3 rooms on each floor. Print a series of strings in the format of "[Block][Floor number][Room number] to be printed out as room tags. (e.g. A11, A12, A13, A21..., C41, C42, C43)