25 21
D BBBB BAABBA DBBBDBDCB BBA BCBDB ABBB BBDBAB DBABBBBBBBB BBDABB ABBBCCADBA AABCABBBBB BBBBABABBA BBCDACBCBBABABBB D BBBBBBADDCC BBBBCBBAB BBDA BBABABBDA AADCDBBBBCDC BBBBCDCBCADABBB 
A BBAC BBCBBA ADBBBBABB BAB DBDDA BBDD AAABDB ACBDBBBBCBA BBCBBD BCBCBBBBBB AAABCBBBBB BBBBBAABBA CBBBDBCBBDBDBCBA B DBBBABBDBBA DABDDCBBB DBAB ABBBBBBBB BADBACDBBBAD BDBCBBBBACBBAAB