ABRO> ;
--- Output:
ABRO> A B;
--- Output: O
ABRO> A B;
--- Output:
ABRO> R;
--- Output:
ABRO> A B;
--- Output: O
ABRO> A B;
--- Output:
ABRO> R;
--- Output:
ABRO> B;
--- Output:
ABRO> A;
--- Output: O
ABRO> A;
--- Output:
ABRO> B;
--- Output:
ABRO> R B;
--- Output:
ABRO> A;
--- Output:
ABRO> ;
--- Output:
ABRO> B;
--- Output: O