: Test for source tree numbering : Level A 1: Level B : Level C 1: Level D 1: Level E 1-1: Level E, again 1: Level E, again : Level A 1: Level B : Level C 1: Level D 1: Level E 1-1: Level E, again 2: Level D 2: Level E 2-1: Level E, again 2: Level E, again : Level C 1: Level D 2: Level B