a-ak aaaa aaab aaba aabb aabt aaka aata aatk aatt abaa abab abag abak abat abb- abba abbb abbt abta agag agat agba agga agta akaa akka at-t ataa atab atak atat atka atkt atta baaa baak baat baba babb baga bagg bagt bak- baka bakt bata batt bbbb bbga btaa bttb gaba gabb gabt gaga gagg gata gatt gbag ggbt gggg gtaa gtta kaaa kaab kaag kaak kaat kaba kabb kabg kag- kaga kagb kagg kagt kaka kakk kakt kat- kata katb katg katk katt kbaa kbab kbak kbat kbba kbbb kbbg kbbk kbbt kbga kbgb kbgg kbgt kbkb kbkg kbkk kbta kbtb kbtk kbtt kgab kgak kgba kgbb kgbt kgga kggg kgtk kkaa kkag kkat kkba kkbb kkbg kkbt kkgb kkkk kktk ktaa ktag ktak ktat ktba ktbb ktbg ktbt ktga ktgg ktkb ktkk ktkt kttg kttk kttt taa- taag taat taba tabb taga tagg taka takk takt tata tatb tatt tbta tkkg ttab ttbb ttkg tttt